mpeg4: disable checked bitstream reader, overreads are not possible.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 06192e42fd)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/mpeg4video_parser.c

@@ -20,6 +20,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#define UNCHECKED_BITSTREAM_READER 1
+
 #include "parser.h"
 #include "mpegvideo.h"
 #include "mpeg4video.h"