pinctrl: mediatek: Modify pinctrl bindings for mt6397.

Since 6397 is no need to support interrupt controller,
moving interrupt controller relate property to optional list.
Also adding mt8173 and mt8127 to bindings.

Signed-off-by: Hongzhou Yang <hongzhou.yang@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>