dt-bindings: gpu: mali-bifrost: Add compatible for MT8188 SoC

Add a compatible for the MediaTek MT8188 SoC, with an integrated
ARM Mali G57 MC3 (Valhall-JM) GPU.
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240611085602.491324-2-angelogioacchino.delregno@collabora.com

Documentation/devicetree/bindings/gpu/arm,mali-bifrost.yaml

@@ -34,6 +34,7 @@ properties:
           - const: arm,mali-valhall-jm # Mali Valhall GPU model/revision is fully discoverable
       - items:
           - enum:
+              - mediatek,mt8188-mali
               - mediatek,mt8192-mali
           - const: arm,mali-valhall-jm # Mali Valhall GPU model/revision is fully discoverable
 
@@ -195,7 +196,9 @@ allOf:
       properties:
         compatible:
           contains:
-            const: mediatek,mt8183b-mali
+            enum:
+              - mediatek,mt8183b-mali
+              - mediatek,mt8188-mali
     then:
       properties:
         power-domains: