nx-X11/programs/Xserver/{hw/nxagent/NX,render/}picture.c: add and use new function ReduceCompositeOp().

More or less just an optimization for more "trivial" composite operations
requiring less work, but syncs up the newer X.Org Server and nx-libs a bit
more.

nx-X11/programs/Xserver/composite/Imakefile: add new file to SRCS and OBJS and define -DNXAGENT_SERVER while building the Composite extension to disable some code that depends upon a newer X.Org architecture.

misc nx-X11/{programs/Xserver/composite,include/extensions}: update to Composite 0.4 - with changes where neccessary and rough edges.

nx-X11/programs/Xserver/{dix/{colormap.c,window.c},hw/nxagent/NXwindow.c,include/{colormap,window{,str}}.h}: backport features needed for Composite 0.4.

Attributes GH PR #102: https://github.com/ArcticaProject/nx-libs/pull/102

 Amends the following compiler warning

 Display.c: In function ‘nxagentMakeIcon’:
 Display.c:1949:18: warning: assignment from incompatible pointer type
      agentIconData=x2goagentIconData;
                  ^
 Display.c:1954:18: warning: assignment from incompatible pointer type
      agentIconData=nxagentIconData;
                  ^
 Display.c:2001:41: warning: passing argument 3 of ‘XpmCreatePixmapFromData’ from incompatible pointer type
                                          agentIconData,
                                          ^
 In file included from Icons.h:22:0,
                  from Display.c:67:
 X11/include/xpm_nxagent.h:242:6: note: expected ‘char **’ but argument is of type ‘char *’
  FUNC(XpmCreatePixmapFromData, int, (Display *display,
       ^
 X11/include/xpm_nxagent.h:230:32: note: in definition of macro ‘FUNC’
  #define FUNC(f, t, p) extern t f p

hw/nxagent/Display.c: Define Pixmap from XlibPixmap before including Icons.h (which includes hw/nxagent/X11/include/xpm_nxagent.h).

hw/nxagent/Holder.c: Define Pixmap from XlibPixmap before including hw/nxagent/X11/include/xpm_nxagent.h.

 Amends the following compiler warnings:

 ```
 NXmiexpose.c:904:18: warning: ‘newValues[2].ptr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
    gcval[i++].ptr = newValues[TILE].ptr;
                   ^
 NXmiexpose.c:914:24: warning: ‘newValues[1].val’ may be used uninitialized in this function [-Wmaybe-uninitialized]
       if ( pGC->fgPixel != newValues[FOREGROUND].val) {
                         ^
 ```

 Amends the following compiler warning:

 ```
 Window.c: In function ‘nxagentSetTopLevelEventMask’:
 Window.c:3392:31: warning: ‘attributes.event_mask’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      Mask tmp_mask = attributes.event_mask;
                                ^
 ```

 Amends the following compiler warning:

 ```
 Colormap.c: In function ‘nxagentReconnectAllColormap’:
 Colormap.c:575:7: warning: variable ‘flexibility’ set but not used [-Wunused-but-set-variable]
    int flexibility;
        ^
 ```

 Amends the following compiler warning:

 ```
 GCOps.c: In function ‘nxagentCopyArea’:
 GCOps.c:597:7: warning: variable ‘oldDstxyValue’ set but not used [-Wunused-but-set-variable]
    int oldDstxyValue;
        ^
 ```

 Amends the following compiler warning:

 ```
 GC.c: In function ‘nxagentReconnectAllGCs’:
 GC.c:1154:7: warning: variable ‘flexibility’ set but not used [-Wunused-but-set-variable]
    int flexibility;
        ^
 ```

hw/nxagent/Events.c: Only declare and assign message_data and box variables if compiled with -DTEST / -DDEBUG (plus drop commented out code).

 Amends the following compiler warnings:

 ```
 Events.c: In function ‘nxagentHandleClientMessageEvent’:
 Events.c:2694:13: warning: variable ‘message_data’ set but not used [-Wunused-but-set-variable]
        char *message_data;
              ^
 Events.c: In function ‘nxagentClipAndSendExpose’:
 Events.c:4313:10: warning: variable ‘box’ set but not used [-Wunused-but-set-variable]
    BoxRec box;
           ^
 ```

 Amends the following compiler warnings:

 ```
 Display.c: In function ‘nxagentReconnectDisplay’:
 Display.c:2449:19: warning: variable ‘packQuality’ set but not used [-Wunused-but-set-variable]
    int packMethod, packQuality;
                    ^
 Display.c:2449:7: warning: variable ‘packMethod’ set but not used [-Wunused-but-set-variable]
    int packMethod, packQuality;
        ^
 ```

 Amends the following compiler warning:

 ```
 NXrender.c: In function ‘swapStops’:
 NXrender.c:3036:13: warning: variable ‘colors’ set but not used [-Wunused-but-set-variable]
      CARD16 *colors;
              ^
 ```

 We don't define HAVE_STDINT_H anywhere and it should be more safe using
 the system's definition of UINT32_MAX.

 This requires adaptations of arguments' types for the external
 references to MakeAtom() and CopyISOLatin1Lowered().

 These adaptations have been required in Xserver/include/dix.h,
 Xserver/include/dixfonts.c Xserver/dix/atom.c, Xserver/dix/dixutils.c,
 Xserver/os/oscolor.c.

hw/nxagent/NXdixfonts.c: Don't include <X11/fonts/fontstruct.h>. No symbol needed from that header file.

 Amends the following compiler warnings:

 ```
 NXpicture.c: In function ‘nxagentReconnectPictFormat’:
 NXpicture.c:2148:9: warning: variable ‘pBool’ set but not used [-Wunused-but-set-variable]
    Bool *pBool;
         ^
 NXpicture.c:2147:17: warning: variable ‘pFormat’ set but not used [-Wunused-but-set-variable]
    PictFormatPtr pFormat;
                  ^
 ```

 Amends the following compiler warning:

 ```
 NXglyphcurs.c: In function ‘ServerBitsFromGlyph’:
 NXglyphcurs.c:109:17: warning: variable ‘gcval’ set but not used [-Wunused-but-set-variable]
     ChangeGCVal gcval[3];
                 ^
 ```

 Amends the following compiler warning:

 ```
 Keyboard.c: In function ‘nxagentKeyboardProc’:
 Keyboard.c:688:7: warning: variable ‘ret’ set but not used [-Wunused-but-set-variable]
    int ret;
        ^
 ```

 Amends the following compiler warning:

 ```
 Handlers.c: In function ‘nxagentShadowBlockHandler’:
 Handlers.c:732:7: warning: variable ‘result’ set but not used [-Wunused-but-set-variable]
    int result;
        ^
 ```

 Amends the following compiler warning:

 ```
 Keyboard.c: In function ‘nxagentNotifyKeyboardChanges’:
 Keyboard.c:1211:16: warning: variable ‘xkb’ set but not used [-Wunused-but-set-variable]
      XkbDescPtr xkb;
                 ^
 ```

 These can be dropped after we have turned REGION_* macros into
 static inline function calls in some of the previous commits.

 Amends the following compiler warnings:

 ```
 Screen.c: In function ‘nxagentCreateIconWindow’:
 Screen.c:394:15: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘Window’ [-Wformat=]
                nxagentIconWindow);
                ^
 Screen.c: In function ‘nxagentSetScreenSaverTime’:
 Screen.c:456:19: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘CARD32’ [-Wformat=]
                    ScreenSaverTime, ScreenSaverInterval);
                    ^
 Screen.c:456:19: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 4 has type ‘CARD32’ [-Wformat=]
 Screen.c:476:19: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘CARD32’ [-Wformat=]
                    ScreenSaverTime, ScreenSaverInterval);
                    ^
 Screen.c:476:19: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 4 has type ‘CARD32’ [-Wformat=]
 Screen.c: In function ‘nxagentOpenScreen’:
 Screen.c:1234:19: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘VisualID’ [-Wformat=]
                    visuals[numVisuals].vid);
                    ^
 Screen.c:1274:23: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘VisualID’ [-Wformat=]
                        depths[depthIndex].depth);
                        ^
 Screen.c:1282:17: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 4 has type ‘VisualID’ [-Wformat=]
                  defaultVisualIndex, visuals[defaultVisualIndex].vid);
                  ^
 Screen.c:1319:19: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 6 has type ‘VisualID’ [-Wformat=]
                    rootDepth, defaultVisual);
                    ^
 Screen.c:1336:19: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 6 has type ‘VisualID’ [-Wformat=]
                    rootDepth, defaultVisual);
                    ^
 Screen.c:1348:19: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 6 has type ‘VisualID’ [-Wformat=]
                    rootDepth, defaultVisual);
                    ^
 Screen.c:1357:19: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 6 has type ‘VisualID’ [-Wformat=]
                    rootDepth, defaultVisual);
                    ^
 Screen.c:1723:21: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘Window’ [-Wformat=]
                      nxagentDefaultWindows[pScreen->myNum]);
                      ^
 Screen.c:1763:19: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘Window’ [-Wformat=]
                    nxagentDefaultWindows[pScreen->myNum]);
                    ^
 Screen.c:1775:17: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘Window’ [-Wformat=]
                  nxagentDefaultWindows[pScreen->myNum]);
                  ^
 Screen.c:1790:17: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘Window’ [-Wformat=]
                  nxagentDefaultWindows[pScreen->myNum]);
                  ^
 Screen.c: In function ‘nxagentShadowAdaptDepth’:
 Screen.c:3189:14: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’ [-Wformat=]
               pVisual -> red_mask, pVisual -> green_mask, pVisual -> blue_mask);
               ^
 Screen.c:3189:14: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 4 has type ‘long unsigned int’ [-Wformat=]
 Screen.c:3189:14: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 5 has type ‘long unsigned int’ [-Wformat=]
 Screen.c:3198:15: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long unsigned int’ [-Wformat=]
                redMask, greenMask, blueMask);
                ^
 Screen.c:3198:15: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 4 has type ‘long unsigned int’ [-Wformat=]
 Screen.c:3198:15: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 5 has type ‘long unsigned int’ [-Wformat=]
 ```

 Amends the following compiler warnings:

 ```
 Screen.c: In function ‘nxagentReconnectScreen’:
 Screen.c:3547:7: warning: variable ‘flexibility’ set but not used [-Wunused-but-set-variable]
   int flexibility;
       ^
 Screen.c: In function ‘nxagentAdjustRandRXinerama’:
 Screen.c:3746:12: warning: unused variable ‘j’ [-Wunused-variable]
      int i, j;
             ^
 Screen.c: In function ‘nxagentSaveAreas’:
 Screen.c:4116:15: warning: variable ‘pDrawable’ set but not used [-Wunused-but-set-variable]
    DrawablePtr pDrawable;
                ^
 Screen.c: In function ‘nxagentRestoreAreas’:
 Screen.c:4236:15: warning: variable ‘pDrawable’ set but not used [-Wunused-but-set-variable]
    DrawablePtr pDrawable;
                ^
 ```

hw/nxagent/Screen.h: Provide prototype for nxagentAdjustRandRXinerama(). Avoid implicit-declaration compiler warning.

 Amends the following compiler warning:

 ```
 Screen.c:3716:5: warning: implicit declaration of function ‘nxagentAdjustRandRXinerama’ [-Wimplicit-function-declaration]
      nxagentAdjustRandRXinerama(pScreen);
      ^
 ```

 Use MIN(A,B) macro as defined in Utils.h. Add MAX(A,B) macro in Utils.h,
 as well. Don't have another set of MIN/MAX macro definitions in
 Screen.c.

 Amends the following compiler warnings:

 ```
 Screen.c:3600:0: warning: "MIN" redefined
  #define MIN(a,b) ((a) < (b)) ? (a) : (b);
  ^
 In file included from Screen.c:78:0:
 Utils.h:36:0: note: this is the location of the previous definition
  #define MIN(A, B) ( (A) < (B) ? (A) : (B) )
  ^
 ```

 Amends the following compiler warning:

 ```
 Window.c:2179:24: warning: variable ‘changes’ set but not used [-Wunused-but-set-variable]
         XWindowChanges changes;
                        ^
 ```

 Amends the following compiler warning:

 ```
 Pixmap.c: In function ‘nxagentDisconnectPixmap’:
 Pixmap.c:755:9: warning: variable ‘pBool’ set but not used [-Wunused-but-set-variable]
    Bool *pBool;
          ^
 ```

 Amends the following the compiler warnings:

 ```
 Extensions.c: In function ‘nxagentRandRInitSizes’:
 Extensions.c:159:16: warning: unused variable ‘pRandRScrPriv’ [-Wunused-variable]
    rrScrPrivPtr pRandRScrPriv = rrGetScrPriv(pScreen);
                 ^
 Extensions.c: In function ‘nxagentRandRSetConfig’:
 Extensions.c:263:16: warning: unused variable ‘pRandRScrPriv’ [-Wunused-variable]
    rrScrPrivPtr pRandRScrPriv;
                 ^
 Extensions.c: In function ‘nxagentRandRScreenSetSize’:
 Extensions.c:322:16: warning: unused variable ‘pRandRScrPriv’ [-Wunused-variable]
    rrScrPrivPtr pRandRScrPriv;
                 ^
 ```

hw/nxagent/Rootless.c: Type cast type Atom to type long unsigned int before handing it over to %lu in fprintf().

 Amends the following compiler warnings:

 ```
 Rootless.c: In function ‘nxagentExportProperty’:
 Rootless.c:775:21: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 3 has type ‘Atom’ [-Wformat=]
                      "Property [%lu] too long.\n", propertyX);
                      ^
 ```

 Amends the following compiler warning:

 ```
 Splash.c: In function ‘nxagentPaintLogo’:
 Splash.c:168:13: warning: unused variable ‘m’ [-Wunused-variable]
    XPoint    m[12];
              ^
 ```

 Amends the following compiler warning:

 ```
 Clipboard.c: In function ‘nxagentRequestSelection’:
 Clipboard.c:272:7: warning: variable ‘result’ set but not used [-Wunused-but-set-variable]
    int result;
        ^
 ```