Input: add keypad driver for w90p910

Add keypad driver for the 4x4 keypad on an evaluation board based
on w90p910.

Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>
Reviewed-by: Trilok Soni <soni.trilok@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
4 files changed