dt-bindings: gpu: mali-utgard: Add Rockchip RK3128 compatible

Rockchip RK312x SoC family has a Mali400 MP2.
Add a compatible for it.
Signed-off-by: Alex Bee <knaerzche@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20231202125144.66052-4-knaerzche@gmail.com

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

@@ -29,6 +29,7 @@ properties:
               - allwinner,sun50i-a64-mali
               - rockchip,rk3036-mali
               - rockchip,rk3066-mali
+              - rockchip,rk3128-mali
               - rockchip,rk3188-mali
               - rockchip,rk3228-mali
               - samsung,exynos4210-mali