pinctrl: mediatek: add no eint function for pin define

Add NO_EINT_SUPPORT back to pinctrl-mtk-common-v2.h as the alias of
EINT_NA to indicate that some pin not capable of being controlled as eint
and that is required by pinctrl-paris based driver as old
pinctrl-mtk-common.h already had.

Signed-off-by: Mars Cheng <mars.cheng@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>