util/*: update include guards

src/util/ConstBuffer.hxx

@@ -27,8 +27,8 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef CONST_BUFFER_HPP
-#define CONST_BUFFER_HPP
+#ifndef CONST_BUFFER_HXX
+#define CONST_BUFFER_HXX
 
 #include "Compiler.h"
 

src/util/StaticFifoBuffer.hxx

@@ -27,8 +27,8 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef STATIC_FIFO_BUFFER_HPP
-#define STATIC_FIFO_BUFFER_HPP
+#ifndef STATIC_FIFO_BUFFER_HXX
+#define STATIC_FIFO_BUFFER_HXX
 
 #include "WritableBuffer.hxx"
 

src/util/StringBuffer.hxx

@@ -27,8 +27,8 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef STRING_BUFFER_HPP
-#define STRING_BUFFER_HPP
+#ifndef STRING_BUFFER_HXX
+#define STRING_BUFFER_HXX
 
 #include <array>
 

src/util/StringUtil.hxx

@@ -17,8 +17,8 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#ifndef MPD_STRING_UTIL_HXX
-#define MPD_STRING_UTIL_HXX
+#ifndef STRING_UTIL_HXX
+#define STRING_UTIL_HXX
 
 #include "Compiler.h"
 

src/util/WritableBuffer.hxx

@@ -27,8 +27,8 @@
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef WRITABLE_BUFFER_HPP
-#define WRITABLE_BUFFER_HPP
+#ifndef WRITABLE_BUFFER_HXX
+#define WRITABLE_BUFFER_HXX
 
 #include "Compiler.h"