Allwinner sun4i USB PHY
-----------------------

Required properties:
- compatible : should be one of "allwinner,sun4i-a10-usb-phy",
  "allwinner,sun5i-a13-usb-phy" or "allwinner,sun7i-a20-usb-phy"
- reg : a list of offset + length pairs
- reg-names : "phy_ctrl", "pmu1" and for sun4i or sun7i "pmu2"
- #phy-cells : from the generic phy bindings, must be 1
- clocks : phandle + clock specifier for the phy clock
- clock-names : "usb_phy"
- resets : a list of phandle + reset specifier pairs
- reset-names : "usb0_reset", "usb1_reset" and for sun4i or sun7i "usb2_reset"

Example:
	usbphy: phy@0x01c13400 {
		#phy-cells = <1>;
		compatible = "allwinner,sun4i-a10-usb-phy";
		/* phy base regs, phy1 pmu reg, phy2 pmu reg */
		reg = <0x01c13400 0x10 0x01c14800 0x4 0x01c1c800 0x4>;
		reg-names = "phy_ctrl", "pmu1", "pmu2";
		clocks = <&usb_clk 8>;
		clock-names = "usb_phy";
		resets = <&usb_clk 1>, <&usb_clk 2>;
		reset-names = "usb1_reset", "usb2_reset";
	};
