phy: qcom: Add device tree bindings for IPQ806x SATA PHY

Qualcomm IPQ806x SATA PHY Controller

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SATA PHY nodes are defined to describe on-chip SATA Physical layer controllers.

Each SATA PHY controller should have its own node.

Required properties:

- compatible: compatible list, contains "qcom,ipq806x-sata-phy"

- reg: offset and length of the SATA PHY register set;

- #phy-cells: must be zero

- clocks: must be exactly one entry

- clock-names: must be "cfg"

Example:

	sata_phy: sata-phy@1b400000 {

		compatible = "qcom,ipq806x-sata-phy";

		reg = <0x1b400000 0x200>;

		clocks = <&gcc SATA_PHY_CFG_CLK>;

		clock-names = "cfg";

		#phy-cells = <0>;

	};