drm/mediatek: Set DRM mode configs accordingly

drm/mediatek: Set DRM mode configs accordingly

Set DRM mode configs limitation according to the hardware capabilities
and pass the IGT checks as below:

- The test "graphics.IgtKms.kms_plane" requires a frame buffer with
  width of 4512 pixels (> 4096).
- The test "graphics.IgtKms.kms_cursor_crc" checks if the cursor size is
  defined, and run the test with cursor size from 1x1 to 512x512.

Please notice that the test conditions may change as IGT is updated.

Reviewed-by: CK Hu <ck.hu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20240620-igt-v3-10-a9d62d2e2c7e@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>