dt-bindings: pinctrl: update bindings for MT7986 SoC

This updates bindings for MT7986 pinctrl driver. The
difference of pinctrl between mt7986a and mt7986b is that pin-41 to
pin-65 do not exist on mt7986b

Signed-off-by: Sam Shih <sam.shih@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211022124036.5291-2-sam.shih@mediatek.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>