* Qualcomm Atheros PHY Device Tree binding

Required properties:
- reg: PHY address

Optional properties:
- qca,clk-out-frequency: Clock frequency of the CLK_25M pin in Hz.
	Either 25000000, 50000000, 62500000 or 125000000.
- qca,clk-out-strength: Clock output buffer driver strength.
    Supported values are defined in dt-bindings/net/qca-ar803x.h
- qca,keep-pll-enabled: Keep the PLL running if no link is present.
	Don't go into hibernation mode.
	Only supported on the AR8031/AR8033.
- vddio-supply: RGMII I/O voltage regulator
	Only supported on the AR8031/AR8033.

Optional subnodes:
- vddio-regulator: Initial data for the VDDIO regulator, as covered
    doc/device-tree-bindings/regulator/regulator.txt

Example:
	#include <dt-bindings/net/qca-ar803x.h>

	ethernet-phy@0 {
		reg = <0>;
		qca,clk-out-frequency = <125000000>;
		qca,keep-pll-enabled;

		vddio-supply = <&vddio>;

		vddio: vddio-regulator {
			regulator-min-microvolt = <1800000>;
			regulator-max-microvolt = <1800000>;
		};
	};