dt-bindings: phy: qcom,qmp: Add SM6350 UFS PHY bindings

Document the compatible string for the UFS PHY found in SM6350.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20220321133318.99406-3-luca.weiss@fairphone.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>