[#18517] Python scripts segfault on loading

own error, EXPP_incr_ret from a macro was an implicit decloration in BGL.c
For some reason this only crashed on 64bit linux

To my defence the BGE makes so many warnings that they become usless, need to improve the situation here at some point.

source/blender/python/api2_2x/BGL.h

@@ -304,7 +304,8 @@ typedef struct _Buffer {
 
 #define ret_def_void
 #define ret_set_void
-#define ret_ret_void    return EXPP_incr_ret(Py_None)
+/* would use Py_RETURN_NONE - except for py 2.3 doesnt have it */
+#define ret_ret_void    { Py_INCREF(Py_None); return Py_None; }
 
 #define ret_def_GLint   int ret_int
 #define ret_set_GLint   ret_int=