Bluetooth: Fix L2CAP locking scheme regression

When locking was introduced the error path branch was not taken
into account. Error was found in sparse code checking. Kudos to
Jani Nikula.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/l2cap.c

@@ -1212,6 +1212,7 @@ static void l2cap_monitor_timeout(unsigned long arg)
 	bh_lock_sock(sk);
 	if (l2cap_pi(sk)->retry_count >= l2cap_pi(sk)->remote_max_tx) {
 		l2cap_send_disconn_req(l2cap_pi(sk)->conn, sk);
+		bh_unlock_sock(sk);
 		return;
 	}