ARM: 7562/2: MMCI: fetch pinctrl handle and set default state

This fetches the pinctrl resource for the MMCI driver, and if
a "default" state is found, it is activated.

Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>