Revert revision 1.13. This allows server-side libGLcore (in X.org) to build

with Mesa CVS.  This change was wrong in the first place, and the issue that
necessitated it has been resolved.  For more background on the problem see:

http://marc.theaimsgroup.com/?l=mesa3d-dev&m=111333880529935&w=2

src/mesa/drivers/dri/common/dri_util.c

@@ -51,7 +51,7 @@
 #include "drm_sarea.h"
 #include "glcontextmodes.h"
 
-#ifndef PFNGLXGETMSCRATEOMLPROC
+#ifndef GLX_OML_sync_control
 typedef GLboolean ( * PFNGLXGETMSCRATEOMLPROC) (__DRInativeDisplay *dpy, __DRIid drawable, int32_t *numerator, int32_t *denominator);
 #endif