ahci: st: Provide DT bindings for ST's SATA implementation

STMicroelectronics STi SATA controller

This binding describes a SATA device.

Required properties:

 - compatible	   : Must be "st,sti-ahci"

 - reg		   : Physical base addresses and length of register sets

 - interrupts	   : Interrupt associated with the SATA device

 - interrupt-names :   Associated name must be; "hostc"

 - resets	   : The power-down and soft-reset lines of SATA IP

 - reset-names	   :   Associated names must be; "pwr-dwn" and "sw-rst"

 - clocks	   : The phandle for the clock

 - clock-names	   :   Associated name must be; "ahci_clk"

 - phys		   : The phandle for the PHY device

 - phy-names	   :   Associated name must be; "ahci_phy"

Example:

	sata0: sata@fe380000 {

		compatible      = "st,sti-ahci";

		reg             = <0xfe380000 0x1000>;

		interrupts      = <GIC_SPI 157 IRQ_TYPE_NONE>;

		interrupt-names = "hostc";

		phys	        = <&miphy365x_phy MIPHY_PORT_0 MIPHY_TYPE_SATA>;

		phy-names       = "ahci_phy";

		resets	        = <&powerdown STIH416_SATA0_POWERDOWN>,

				  <&softreset STIH416_SATA0_SOFTRESET>;

		reset-names     = "pwr-dwn", "sw-rst";

		clocks	        = <&clk_s_a0_ls CLK_ICN_REG>;

		clock-names     = "ahci_clk";

	};