dt-bindings: phy: rockchip,rk3588-hdptx-phy: Add #clock-cells

The HDMI PHY can be used as a clock provider on RK3588 SoC, hence add
the necessary '#clock-cells' property.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://lore.kernel.org/r/20240620-rk3588-hdmiphy-clkprov-v2-3-6a2d2164e508@collabora.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/phy/rockchip,rk3588-hdptx-phy.yaml

@@ -27,6 +27,9 @@ properties:
       - const: ref
       - const: apb
 
+  "#clock-cells":
+    const: 0
+
   "#phy-cells":
     const: 0