arm64: dts: mediatek: Add MT8186 Steelix platform based Rusty

MT8186 Rusty, otherwise known as the Lenovo 100e Chromebook Gen 4, is an
MT8186 based laptop. It is based on the "Steelix" design. Being a laptop
instead of a convertible device, there is no touchscreen or stylus.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240126083802.2728610-9-wenst@chromium.org


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