h263dec: disable coded dimensions = 0 handling

This code causes infinite loops
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/h263dec.c

@@ -598,7 +598,7 @@ retry:
         /* FIXME: By the way H263 decoder is evolving it should have */
         /* an H263EncContext                                         */
 
-    if (!avctx->coded_width || !avctx->coded_height) {
+    if ((!avctx->coded_width || !avctx->coded_height) && 0) {
         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
 
         s->parse_context.buffer=0;