dt-bindings: phy: qmp: Add support for QMP phy in IPQ8074

IPQ8074 uses QMP PHY controller that provides support to PCIe and
USB. Adding DT binding information for the same.
Reviewed-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Signed-off-by: Varadarajan Narayanan <varada@codeaurora.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

Documentation/devicetree/bindings/phy/qcom-qmp-phy.txt

@@ -6,6 +6,7 @@ controllers on Qualcomm chipsets, such as, PCIe, UFS, and USB.
 
 Required properties:
  - compatible: compatible list, contains:
+	       "qcom,ipq8074-qmp-pcie-phy" for PCIe phy on IPQ8074
 	       "qcom,msm8996-qmp-pcie-phy" for 14nm PCIe phy on msm8996,
 	       "qcom,msm8996-qmp-usb3-phy" for 14nm USB3 phy on msm8996.
 
@@ -38,6 +39,8 @@ Required properties:
 		 "phy", "common", "cfg".
 		For "qcom,msm8996-qmp-usb3-phy" must contain
 		 "phy", "common".
+		For "qcom,ipq8074-qmp-pcie-phy" must contain:
+		 "phy", "common".
 
  - vdda-phy-supply: Phandle to a regulator supply to PHY core block.
  - vdda-pll-supply: Phandle to 1.8V regulator supply to PHY refclk pll block.
@@ -63,6 +66,11 @@ Required properties for child node:
  - clock-output-names: Name of the PHY clock that will be the parent for
 		       the above pipe clock.
 
+	For "qcom,ipq8074-qmp-pcie-phy":
+		- "pcie20_phy0_pipe_clk"	Pipe Clock parent
+			(or)
+		  "pcie20_phy1_pipe_clk"
+
  - resets: a list of phandles and reset controller specifier pairs,
 	   one for each entry in reset-names.
  - reset-names: Must contain following for pcie qmp phys: