dt-bindings: phy: Add QMP UFS PHY comptible for SM8550

Document the QMP UFS PHY compatible for SM8550.

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

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

···
     enum:
       - qcom,sc8280xp-qmp-ufs-phy
       - qcom,sm6125-qmp-ufs-phy
+      - qcom,sm8550-qmp-ufs-phy
 
   reg:
     maxItems: 1