dt-bindings: phy: qcom,qusb2: Document IPQ5424 compatible

Document the compatible string used for the qusb2 phy in IPQ5424.

Acked-by: Conor Dooley <[e-mail]>
Signed-off-by: Varadarajan Narayanan <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/qcom,qusb2-phy.yaml

···
     oneOf:
       - items:
           - enum:
+              - qcom,ipq5424-qusb2-phy
               - qcom,ipq6018-qusb2-phy
               - qcom,ipq8074-qusb2-phy
               - qcom,ipq9574-qusb2-phy