dt-bindings: display: mediatek: merge: Add compatible for MediaTek MT6795

Add a compatible string for MediaTek Helio X10 MT6795's MERGE block: this
is the same as MT8173.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20230412112739.160376-12-angelogioacchino.delregno@collabora.com/Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

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

@@ -24,6 +24,9 @@ properties:
       - enum:
           - mediatek,mt8173-disp-merge
           - mediatek,mt8195-disp-merge
+      - items:
+          - const: mediatek,mt6795-disp-merge
+          - const: mediatek,mt8173-disp-merge
 
   reg:
     maxItems: 1