dt-bindings: display: mediatek: ovl: add compatible for MT8195

Add a compatible string for the OVL block in MediaTek MT8195 that
is controlled by MDP3.
Signed-off-by: Moudy Ho <moudy.ho@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

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

@@ -26,6 +26,7 @@ properties:
           - mediatek,mt8173-disp-ovl
           - mediatek,mt8183-disp-ovl
           - mediatek,mt8192-disp-ovl
+          - mediatek,mt8195-mdp3-ovl
       - items:
           - enum:
               - mediatek,mt7623-disp-ovl