arm64: dts: mediatek: cherry: Add I2C-HID touchscreen on I2C4

This platform carries a HID compatible I2C touchscreen on the i2c4 bus,
but it may be at a different address, depending on the board model.
Add the node for a touchscreen at 0x10, but enable it only in the
final board dts.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220704101321.44835-12-angelogioacchino.delregno@collabora.com


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>