clk_disable() in remove method is not needed since we already
have clk_disable in pxa27x_keypad_close().

Also make sure the driver uses resource_size() and helpers from
include/input/matrix_keypad.h
Tested-by: Mike Rapoport <mike@compulab.co.il>
Acked-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>