Input: wacom - revert "Cintiq 21UX2 does not have menu strips"

This reverts commit 71c86ce5.
The 21UX2 does have touchstrips, but they are in a somewhat-
hidden location.

Signed-off-by: Jason Gerecke <killertofu@gmail.com>
Acked-by: Ping Cheng <pinglinux@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>