dt-bindings: pinctrl: Add MediaTek MT6795 pinctrl bindings

Add devicetree and pinfunc bindings for MediaTek Helio X10 MT6795.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220517083957.11816-2-angelogioacchino.delregno@collabora.com


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