File ClanLib-2.3.6-fix-opengl.patch of Package clanlib

Index: ClanLib-2.3.6/Sources/API/GL1/opengl1_defines.h
===================================================================
--- ClanLib-2.3.6.orig/Sources/API/GL1/opengl1_defines.h
+++ ClanLib-2.3.6/Sources/API/GL1/opengl1_defines.h
@@ -44,6 +44,11 @@
 #ifndef CL_DISPLAYDEFINES_DEFINES
 #define CL_DISPLAYDEFINES_DEFINES
 
+/* newer Mesa defines this and creates a conflict */
+#ifdef GL_TYPE
+#undef GL_TYPE
+#endif
+
 #include <cstddef>
 
 #ifndef __APPLE__