pinctrl: mediatek: select GPIOLIB

pinctrl: mediatek: select GPIOLIB

Removing the linux/gpio.h include means we no longer have a declaration
of gpiochip_lock_as_irq() when CONFIG_GPIOLIB is disabled:

drivers/pinctrl/mediatek/mtk-eint.c: In function 'mtk_eint_irq_request_resources':
drivers/pinctrl/mediatek/mtk-eint.c:247:8: error: implicit declaration of function 'gpiochip_lock_as_irq'; did you mean 'spin_lock_irq'? [-Werror=implicit-function-declaration]
drivers/pinctrl/mediatek/mtk-eint.c: In function 'mtk_eint_irq_release_resources':
drivers/pinctrl/mediatek/mtk-eint.c:272:2: error: implicit declaration of function 'gpiochip_unlock_as_irq'; did you mean 'spin_unlock_irq'? [-Werror=implicit-function-declaration]

Select it explictly instead.

Fixes: c1bdf8c198e8 ("pinctrl: Include <linux/gpio/driver.h> nothing else")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>