arm64: remove select PINCTRL_ROCKCHIP from ARCH_ROCKCHIP

Prepare to make pinctrl driver of rockchip to be module able, this patch
remove the select of PINCTRL_ROCKCHIP from ARCH_ROCKCHIP.

Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
Link: https://lore.kernel.org/r/20210305003907.1692515-2-jay.xu@rock-chips.com


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