media: mceusb: return without resubmitting URB in case of -EPROTO error.

Syzkaller reported a warning called "rcu detected stall in dummy_timer".

The error seems to be an error in mceusb_dev_recv(). In the case of
-EPROTO error, the routine immediately resubmits the URB. Instead it
should return without resubmitting URB.

Reported-by:  <syzbot+4d3749e9612c2cfab956@syzkaller.appspotmail.com>
Signed-off-by: Rajat Asthana <rajatasthana4@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>