$NetBSD$

Tweak includes so that they can be found.
Latter include is due to CPAN bug 19155.

--- src/OpenGL.xs.orig	2004-09-24 00:36:56.000000000 +0000
+++ src/OpenGL.xs
@@ -12,8 +12,8 @@
 
 #include <SDL.h>
 
-#include <gl.h>
-#include <glu.h>
+#include <GL/gl.h>
+#include <GL/glu.h>
 
 #ifdef USE_THREADS
 #define HAVE_TLS_CONTEXT
@@ -23,7 +23,7 @@
 #define GL_ALL_CLIENT_ATTRIB_BITS 0xFFFFFFF
 #endif /* GL_ALL_CLIENT_BITS */  
 
-#include "../defines.h"
+#include "../src/defines.h"
 
 SV* sdl_perl_nurbs_error_hook;
 void
