patch [#6213] msvc had problems with GL_CLAMP_TO_EDGE being undefined

on some systems.  If its undefined define it.

Kent

source/blender/src/drawmesh.c

@@ -33,10 +33,6 @@
 #include <string.h>
 #include <math.h>
 
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
 #include "MEM_guardedalloc.h"
 
 #include "BLI_blenlib.h"
@@ -84,6 +80,10 @@
 #include "blendef.h"
 #include "nla.h"
 
+#ifndef GL_CLAMP_TO_EDGE
+#define GL_CLAMP_TO_EDGE                        0x812F
+#endif
+
 //#include "glext.h"
 /* some local functions */
 #if defined(GL_EXT_texture_object) && (!defined(__sun__) || (!defined(__sun))) && !defined(__APPLE__) && !defined(__linux__) && !defined(WIN32)