dt-bindings: power: Add MT8188 power domains

Add power domains dt-bindings for MT8188.

Signed-off-by: Garmin.Chang <Garmin.Chang@mediatek.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20221223080553.9397-2-Garmin.Chang@mediatek.com
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>