Fix regression introduced by r12929.

num_coeffs is just one byte.
It would make no sense for num_coeffs to be as high as 2^32.

Originally committed as revision 12931 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/mimic.c

@@ -293,7 +293,8 @@ static int mimic_decode_frame(AVCodecContext *avctx, void *data,
     height     = bytestream_get_le16(&buf);
     buf       += 4; /* some constant */
     is_pframe  = bytestream_get_le32(&buf);
-    num_coeffs = bytestream_get_le32(&buf);
+    num_coeffs = bytestream_get_byte(&buf);
+    buf       += 3; /* some constant */
 
     if(!ctx->avctx) {
         int i;