#undef DATADIR before inclusion of windows.h patch by ("Sascha Sommer" <saschasommer at freenet dot de>)

Originally committed as revision 1749 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/os_support.h

@@ -11,6 +11,7 @@
  */
 
 #ifdef __MINGW32__
+#  undef DATADIR /* clashes with /usr/include/w32api/objidl.h */
 #  include <windows.h>
 #  define usleep(t)    Sleep((t) / 1000)
 #endif