dt-bindings: phy: qcom,sc8280xp-qmp-pcie-phy: Document the X1E80100 QMP PCIe PHY Gen4 x4

The sixth PCIe instance on X1E80100 can be used in either 4-lane mode or
2-lane mode. Document the 4-lane mode as a separate compatible.

Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Reviewed-by: Johan Hovold <[e-mail]>
Signed-off-by: Abel Vesa <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml

···
       - qcom,sm8650-qmp-gen4x2-pcie-phy
       - qcom,x1e80100-qmp-gen3x2-pcie-phy
       - qcom,x1e80100-qmp-gen4x2-pcie-phy
+      - qcom,x1e80100-qmp-gen4x4-pcie-phy
 
   reg:
     minItems: 1
···
           contains:
             enum:
               - qcom,sc8280xp-qmp-gen3x4-pcie-phy
+              - qcom,x1e80100-qmp-gen4x4-pcie-phy
     then:
       properties:
         reg:
···
               - qcom,sc8280xp-qmp-gen3x1-pcie-phy
               - qcom,sc8280xp-qmp-gen3x2-pcie-phy
               - qcom,sc8280xp-qmp-gen3x4-pcie-phy
+              - qcom,x1e80100-qmp-gen4x4-pcie-phy
     then:
       properties:
         clocks: