Input: nomadik-ske-keypad - convert to using SIMPLE_DEV_PM_OPS

Also proper guard for system suspend/resume methods is CONFIG_PM_SLEEP,
not CONFIG_PM.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>