pinctrl: nomadik:remove unneeded variable

ret is unneeded, just return 0.

Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/1585554986-26521-1-git-send-email-dingxiang@cmss.chinamobile.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>