USB: VID/PID update for sierra

Adds VID/PID for the MC8775 found internally in the Thinkpad X61s laptop
(and likely others). For commercial reasons the driver maintainer cannot
add VID/PIDs for laptop OEM devices himself.

Signed-off-by: Kevin R Page <linux-kernel@krp.org.uk>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>