Partly reverts ec30a857, but in a
forward-compatible manner.

Legacy libXfont1 versions are automatically detected by the main
Makefile.

Failed *SUSE checks.

Just copy-paste the initial definition to avoid recursion.

We have no intention to remove system libraries.

We need -std=c99 to be passed through to the build process.

Attributes GH PR #605: https://github.com/ArcticaProject/nx-libs/pull/605

Reviewed-by: Ulrich Sibiller <uli42@gmx.de> --  Thu, 14 Dec 2017 13:15:12 +0000

 They have been flawed ever since nxagent came up, as they were Xfree
 (non-capital f) always, but should have been XFree (capital F, defined
 in Xlibint.h and part of libNX_X11).
 .
 Probably this all should be free() all over the code (bearing in mind,
 that XFree() returns int, not void. But still...

 Fixes ArcticaProject/nx-libs#553.

At least on platforms that support weak dependencies.

Attributes GH PR #333: https://github.com/ArcticaProject/nx-libs/pull/333

 Picked from this X.org commit:

 commit b0dd6be2c8703f7062d45ac9fd646550c7d54e3b
 Author: Jamey Sharp <jamey@minilop.net>
 Date:   Thu Oct 8 13:38:44 2009 +1100

    Cast small-int values through intptr_t when passed as pointers

    On 64-bit systems, int and pointers don't have the same size, so GCC gives
    warnings about casts between int and pointer types. However, in the cases
    covered by this patch, it's always a value that fits in int being stored
    temporarily as a pointer and then converted back later, which is safe.
    Casting through the pointer-sized integer type intptr_t convinces the
    compiler that this is OK.
Signed-off-by: Jamey Sharp <jamey@minilop.net>
Signed-off-by: Daniel Stone <daniel@fooishbar.org>
Backported-to-NX-by: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>
 (Only appropriate location for backporting: Xserver/GL/glx/glxcmds.c).

 Xrm.c: In function 'PutEntry':
 Xrm.c:900:15: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses]
     !quarks[2] != table->leaf)
               ^~

 commit 63ccaec2c39f4b5742383472c951ee2cd35c9e14
 Author: Adam Jackson <ajax@redhat.com>
 Date:   Tue Oct 19 11:59:23 2010 -0400

    render2.c: In function ‘__glXDisp_Map2d’:
    render2.c:127: warning: ‘u1’ may be used uninitialized in this function
    render2.c: In function ‘__glXDisp_Map1d’:
    render2.c:90: warning: ‘u1’ may be used uninitialized in this function

    Remove unnecessary test, and change memcpy to memmove as all users were
    doing overlapping copies.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Daniel Stone <daniel@fooishbar.org>
Backported-to-NX-by: Mike Gabriel <mike.gabriel@das-netzwerkteam.de>

 glxfb.c: In function '__glXFBMemSwapBuffers':
 glxfb.c:117:5: warning: pointer targets in passing argument 10 of 'pGC->ops->PutImage' differ in signedness [-Wpointer-sign]
      buf);
      ^~~
 glxfb.c:117:5: note: expected 'char *' but argument is of type 'GLubyte * {aka unsigned char *}'

 Events.c: In function 'nxagentDumpInputDevicesState':
 Events.c:4662:58: warning: format '%p' expects argument of type 'void *', but argument 3 has type 'DeviceIntPtr {aka struct _DeviceIntRec *}' [-Wformat=]
    fprintf(stderr, "\nKeyboard device state: \n\tdevice [%p]\n\tlast grab time [%lu]"
                                                           ^
 Events.c:4662:82: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'CARD32 {aka unsigned int}' [-Wformat=]
    fprintf(stderr, "\nKeyboard device state: \n\tdevice [%p]\n\tlast grab time [%lu]"
                                                                                  ^
 Events.c:4662:19: warning: format '%p' expects argument of type 'void *', but argument 7 has type 'GrabPtr {aka struct _GrabRec *}' [-Wformat=]
    fprintf(stderr, "\nKeyboard device state: \n\tdevice [%p]\n\tlast grab time [%lu]"
                    ^
 Events.c:4675:66: warning: format '%p' expects argument of type 'void *', but argument 3 has type 'WindowPtr {aka struct _Window *}' [-Wformat=]
      fprintf(stderr, "\nKeyboard grab state: \n\twindow pointer [%p]"
                                                                   ^
 Events.c:4689:59: warning: format '%p' expects argument of type 'void *', but argument 3 has type 'DeviceIntPtr {aka struct _DeviceIntRec *}' [-Wformat=]
        fprintf(stderr, "\nPassive grab state: \n\tdevice [%p]\n\towner events flag [%s]"
                                                            ^
 Events.c:4689:23: warning: format '%lx' expects argument of type 'long unsigned int', but argument 10 has type 'Mask {aka unsigned int}' [-Wformat=]
        fprintf(stderr, "\nPassive grab state: \n\tdevice [%p]\n\towner events flag [%s]"
                        ^
 Events.c:4722:57: warning: format '%p' expects argument of type 'void *', but argument 3 has type 'DeviceIntPtr {aka struct _DeviceIntRec *}' [-Wformat=]
    fprintf(stderr, "\nPointer device state: \n\tdevice [%p]\n\tlast grab time [%lu]"
                                                          ^
 Events.c:4722:81: warning: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'CARD32 {aka unsigned int}' [-Wformat=]
    fprintf(stderr, "\nPointer device state: \n\tdevice [%p]\n\tlast grab time [%lu]"
                                                                                  ^
 Events.c:4722:19: warning: format '%p' expects argument of type 'void *', but argument 7 has type 'GrabPtr {aka struct _GrabRec *}' [-Wformat=]
    fprintf(stderr, "\nPointer device state: \n\tdevice [%p]\n\tlast grab time [%lu]"
                    ^
 Events.c:4735:65: warning: format '%p' expects argument of type 'void *', but argument 3 has type 'WindowPtr {aka struct _Window *}' [-Wformat=]
      fprintf(stderr, "\nPointer grab state: \n\twindow pointer [%p]"
                                                                  ^
 Events.c:4750:61: warning: format '%p' expects argument of type 'void *', but argument 3 has type 'DeviceIntPtr {aka struct _DeviceIntRec *}' [-Wformat=]
          fprintf(stderr, "\nPassive grab state: \n\tdevice [%p]\n\towner events flag [%s]"
                                                              ^
 Events.c:4750:25: warning: format '%lx' expects argument of type 'long unsigned int', but argument 10 has type 'Mask {aka unsigned int}' [-Wformat=]
          fprintf(stderr, "\nPassive grab state: \n\tdevice [%p]\n\towner events flag [%s]"
                          ^

 NXxvdisp.c: In function 'ProcXvDispatch':
 NXxvdisp.c:96:9: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
          else
          ^~~~
 NXxvdisp.c:99:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
              break;
              ^~~~~
 NXxvdisp.c:104:9: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
          else
          ^~~~
 NXxvdisp.c:107:10: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
           break;
           ^~~~~
 NXxvdisp.c:118:2: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   else
   ^~~~
 NXxvdisp.c:121:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
              break;
              ^~~~~
 NXxvdisp.c:126:2: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   else
   ^~~~
 NXxvdisp.c:129:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
              break;
              ^~~~~
 NXxvdisp.c:137:2: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   else
   ^~~~
 NXxvdisp.c:140:13: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
              break;
              ^~~~~
 NXxvdisp.c:146:2: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   else
   ^~~~
 NXxvdisp.c:149:6: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
       break;
       ^~~~~

 NXdispatch.c: In function 'Dispatch':
 NXdispatch.c:309:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
     if (!(dispatchException & DE_TERMINATE))
     ^~
 NXdispatch.c:312:5: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
       while (!dispatchException)
       ^~~~~

 chgfctl.c: In function 'ChangeKbdFeedback':
 chgfctl.c:359:6: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
       else
       ^~~~
 chgfctl.c:361:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'else'
    kctrl.autoRepeats[inx] =
    ^~~~~

Fixes ArcticaProject/nx-libs#516.

debian/control: All Priority: extras packages are required to be changed to Priority: optional by recent Debian Policy.

Attributes GH PR #591: https://github.com/ArcticaProject/nx-libs/pull/591

nxagentInitKeyboardState -> nxagentInitXkbKeyboardState
nxagentHandleKeyboardEvent -> nxagentHandleXkbKeyboardStateEvent