pinctrl: mediatek: Add Pinctrl/GPIO driver for mt8135.
The mediatek SoCs have GPIO controller that handle both the muxing and GPIOs.
The GPIO controller have pinmux, pull enable, pull select, direction and output high/low control.
This driver include common driver and mt8135 part.
The common driver include the pinctrl driver and GPIO driver.
The mt8135 part contain its special device data.
Signed-off-by: Hongzhou Yang <hongzhou.yang@mediatek.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>