Input: via-pmu - add input device support

Add an input device for the button and lid switch so that userspace gets
notified about the user pressing them via the standard input layer.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>