Fixed bad OpenGL includes

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@7909 178a84e3-b1eb-0310-8ba1-8eac791a3b58

src/states_screens/race_gui.cpp

@@ -49,8 +49,11 @@ using namespace irr;
 #include "utils/string_utils.hpp"
 #include "utils/translation.hpp"
 
+#ifdef __APPLE__
 #include <OpenGL/gl.h>
-#include <OpenGL/glu.h>
+#else
+#include <GL/gl.h>
+#endif
 
 /** The constructor is called before anything is attached to the scene node.
  *  So rendering to a texture can be done here. But world is not yet fully