dt-bindings: phy: qcom,qmp: Add IPQ60xx PCIe PHY bindings

Add ipq6018 qmp phy device for the single PCIe serdes lane on IPQ60xx
SoCs.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Link: https://lore.kernel.org/r/be83d8580942ab9d141dffff4e4f33f34a4c9ed9.1620203062.git.baruch@tkos.co.il


Signed-off-by: Vinod Koul <vkoul@kernel.org>