[ARM] pxa/ezx: Keypad configuration

Matrix and single key setups for all phones.

Signed-off-by: Daniel Ribeiro <drwyrm@gmail.com>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Signed-off-by: Eric Miao <eric.miao@marvell.com>