ARM: EXYNOS4: fix incorrect pad configuration for keypad row lines

The keypad controller requires a external pull-up for all the keypad
row lines. Fix the incorrect pad configuration for keypad controller
row lines by enabling the pad pull-up for the all row lines of the
keypad controller.

Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>