drm/mediatek: Support MT8188 VDOSYS1 in display driver

- The mmsys_dev_num in MT8188 VDOSYS0 was set to 1 since
  VDOSYS1 was not available before. Increase it to support
  VDOSYS1 in display driver.
- Add compatible name for MT8188 VDOSYS1
  (shares the same driver data with MT8195 VDOSYS1)

Reviewed-by: CK Hu <ck.hu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231214055847.4936-24-shawn.sung@mediatek.com/


Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>