pinctrl: mediatek: update PCIe mux data for MT7623

MT2701 shares the same driver with MT7623, but there is a slight difference
between their pin functions (e.g., PCIe), so we update the different parts
in pinmux table.

Doing so, SoC could choose the correct mux setting via their own pinfun.h.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Cc: Biao Huang <biao.huang@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>