glapi/glx: Generate dispatch.h so that the xserver can use it

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>

src/mapi/glapi/gen/gl_table.py

@@ -92,7 +92,11 @@ class PrintRemapTable(gl_XML.gl_print_base):
  * named function in the specified dispatch table.
  */
 
+/* GLXEXT is defined when building the GLX extension in the xserver.
+ */
+#if !defined(GLXEXT)
 #include "main/mfeatures.h"
+#endif
 """
 		return