Fix 'make checkheaders' on AltiVec-enabled systems.

Originally committed as revision 25316 to svn://svn.mplayerhq.hu/mplayer/trunk/libswscale

libswscale/swscale_internal.h

@@ -21,6 +21,8 @@
 #ifndef FFMPEG_SWSCALE_INTERNAL_H
 #define FFMPEG_SWSCALE_INTERNAL_H
 
+#include "config.h"
+
 #ifdef HAVE_ALTIVEC_H
 #include <altivec.h>
 #endif