dt-bindings: pinctrl: mediatek: mt8183: Allow gpio-line-names

dt-bindings: pinctrl: mediatek: mt8183: Allow gpio-line-names

Add support for the 'gpio-line-names' property in the MT8183 pinctrl
binding.
This allows naming the GPIOs, which is already done in several
device trees (e.g. mt8183-kukui-jacuzzi.dtsi, mt8183-kukui-kakadu.dtsi,
mt8183-kukui-krane.dtsi), but was previously generating DT schema
warnings.

Signed-off-by: Julien Massot <julien.massot@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/20250801-mtk-dtb-warnings-v1-7-6ba4e432427b@collabora.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>