drm/mediatek: Add display merge advance config API for MT8195

Add merge new advance config API. The original merge API is
mtk_ddp_comp_funcs function prototype. The API interface parameters
cannot be modified, so add a new config API for extension. This is
the preparation for ovl_adaptor merge control.

Signed-off-by: Nancy.Lin <nancy.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20220620091930.27797-5-nancy.lin@mediatek.com/


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