pinctrl_register() returns NULL on error.
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NTony Prisk <linux@prisktech.co.nz>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NOlof Johansson <olof@lixom.net>