dt-bindings: display: mediatek: merge: Add compatible for MT8188

Add compatible name for MediaTek MT8188 MERGE.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20231024130048.14749-4-shawn.sung@mediatek.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

Author: Hsiao Chien Sung

Documentation/devicetree/bindings/display/mediatek/mediatek,merge.yaml

@@ -27,6 +27,9 @@ properties:
       - items:
           - const: mediatek,mt6795-disp-merge
           - const: mediatek,mt8173-disp-merge
+      - items:
+          - const: mediatek,mt8188-disp-merge
+          - const: mediatek,mt8195-disp-merge
 
   reg:
     maxItems: 1