lavf/mov: skip version and flags attributes in mov_read_chan function

Fixes ticket #1764.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/mov.c

@@ -696,6 +696,9 @@ static int mov_read_chan(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     if (atom.size < 16)
         return 0;
 
+    /* skip version and flags */
+    avio_skip(pb, 4);
+
     ff_mov_read_chan(c->fc, pb, st, atom.size - 4);
 
     return 0;