movdec: remove redundant size<=8 check.

Its checked a few lines below too.
The only difference is that empty atoms with size=0 will now get parsed too.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/mov.c

@@ -324,8 +324,6 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom)
                 a.type, (char*)&a.type, (char*)&atom.type, a.size, total_size, atom.size);
         if (a.size == 0) {
             a.size = atom.size - total_size + 8;
-            if (a.size <= 8)
-                break;
         }
         a.size -= 8;
         if (a.size < 0)