dt-bindings: pinctrl: mediatek: mt8186: rename to mediatek,mt8186-pinctrl

Rename pinctrl-mt8186.yaml to mediatek,mt8186-pinctrl.yaml to be on par
with the compatible string and other mediatek dt-binding schemas.

Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230317213011.13656-12-arinc.unal@arinc9.com


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