Input: Wacom driver update

       - add support for Cintiq 21UX
       - fix a Graphire bug
       - merge wacom_intuos3_irq into wacom_intuos_irq
Signed-off-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>