Socionext UniPhier AHCI PHY

This describes the deivcetree bindings for PHY interfaces built into
AHCI glue layer implemented on Socionext UniPhier SoCs.

Required properties:
- compatible: Should contain one of the following:
    "socionext,uniphier-pxs2-ahci-phy" - for PXs2 SoC
    "socionext,uniphier-pxs3-ahci-phy" - for PXs3 SoC
- reg: Specifies offset and length of the register set for the device.
- #phy-cells: Must be zero.
- clocks: A list of phandles to the clock gate for AHCI glue layer.
	According to the clock-names, appropriate clocks are required.
- clock-names:
	"link"        - for PXs2 SoC
	"phy", "link" - for PXs3 SoC
- resets: A list of phandles for the reset control for AHCI glue layer.
	According to the reset-names, appropriate resets are required.
- reset-names:
	"phy", "link" - for PXs2 and PXs3 SoCs

Refer to phy/phy-bindings.txt for the generic PHY binding properties.

Example:

	ahci-glue@65700000 {
		compatible = "socionext,uniphier-pxs3-ahci-glue",
			     "simple-mfd";
		#address-cells = <1>;
		#size-cells = <1>;
		ranges = <0 0x65700000 0x100>;

		ahci_phy: phy@10 {
			compatible = "socionext,uniphier-pxs3-ahci-phy";
			reg = <0x10 0x10>;
			clock-names = "link", "phy";
			clocks = <&sys_clk 28>, <&sys_clk 30>;
			reset-names = "link", "phy";
			resets = <&sys_rst 28>, <&sys_rst 30>;
			#phy-cells = <0>;
		};
		...
	};
