Partially revert changeset 
0208bef609242a2d50b95edc713a41566cae500b:
As pointed by Stefan Ringel <stefan.ringel@arcor.de>, many packets become
damaged by this change. That means that the "size" field of Video/VBI is not
presenting 180 bytes, as it should be expected.
Thanks-to: Stefan Ringel <stefan.ringel@arcor.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
                                break;
                        }
                }
-               if (cpysize < size) {
+               if (ptr + pktsize > endp) {
                        /* End of URB packet, but cmd processing is not
                         * complete. Preserve the state for a next packet
                         */
                        dev->isoc_ctl.size = size - cpysize;
                        dev->isoc_ctl.cmd = cmd;
                        dev->isoc_ctl.pktsize = pktsize - (endp - ptr);
-                       ptr += cpysize;
+                       ptr += endp - ptr;
                } else {
                        dev->isoc_ctl.cmd = 0;
                        ptr += pktsize;