ARM: zynq: Enable pinctrl

Select pinctrl and the Zynq pinctrl driver.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>