mov: check ff_get_wav_header() return value

CC: libav-stable@libav.org
Bug-Id: CID 717497

libavformat/mov.c

@@ -647,9 +647,7 @@ static int mov_read_wfex(MOVContext *c, AVIOContext *pb, MOVAtom atom)
         return 0;
     st = c->fc->streams[c->fc->nb_streams-1];
 
-    ff_get_wav_header(pb, st->codec, atom.size);
-
-    return 0;
+    return ff_get_wav_header(pb, st->codec, atom.size);
 }
 
 static int mov_read_pasp(MOVContext *c, AVIOContext *pb, MOVAtom atom)