arm64: dts: mediatek: mt7988: add I2C controllers

MT7988 has three on-SoC I2C controllers that are the same hardware
blocks as already noticed on MT7981 chipsets.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Link: https://lore.kernel.org/r/20240604064302.487-2-zajec5@gmail.com


Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>