Merge commit 'ff7adead'

* commit 'ff7adead':
  udp: Fix pkt_size management
Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/udp.c

@@ -591,7 +591,7 @@ static int udp_open(URLContext *h, const char *uri, int flags)
             goto fail;
     }
 
-    if (s->pkt_size)
+    if (s->pkt_size > 0)
         h->max_packet_size = s->pkt_size;
 
     p = strchr(uri, '?');