Binding for Texas Instruments interface clock.

This binding uses the common clock binding[1]. This clock is
quite much similar to the basic gate-clock [2], however,
it supports a number of additional features, including
companion clock finding (match corresponding functional gate
clock) and hardware autoidle enable / disable.

[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
[2] Documentation/devicetree/bindings/clock/gpio-gate-clock.yaml

Required properties:
- compatible : shall be one of:
  "ti,omap3-interface-clock" - basic OMAP3 interface clock
  "ti,omap3-no-wait-interface-clock" - interface clock which has no hardware
				       capability for waiting clock to be ready
  "ti,omap3-hsotgusb-interface-clock" - interface clock with USB specific HW
					handling
  "ti,omap3-dss-interface-clock" - interface clock with DSS specific HW handling
  "ti,omap3-ssi-interface-clock" - interface clock with SSI specific HW handling
  "ti,am35xx-interface-clock" - interface clock with AM35xx specific HW handling
  "ti,omap2430-interface-clock" - interface clock with OMAP2430 specific HW
				  handling
- #clock-cells : from common clock binding; shall be set to 0
- clocks : link to phandle of parent clock
- reg : base address for the control register

Optional properties:
- clock-output-names : from common clock binding.
- ti,bit-shift : bit shift for the bit enabling/disabling the clock (default 0)

Examples:
	aes1_ick: aes1_ick@48004a14 {
		#clock-cells = <0>;
		compatible = "ti,omap3-interface-clock";
		clocks = <&security_l4_ick2>;
		reg = <0x48004a14 0x4>;
		ti,bit-shift = <3>;
	};

	cam_ick: cam_ick@48004f10 {
		#clock-cells = <0>;
		compatible = "ti,omap3-no-wait-interface-clock";
		clocks = <&l4_ick>;
		reg = <0x48004f10 0x4>;
		ti,bit-shift = <0>;
	};

	ssi_ick_3430es2: ssi_ick_3430es2@48004a10 {
		#clock-cells = <0>;
		compatible = "ti,omap3-ssi-interface-clock";
		clocks = <&ssi_l4_ick>;
		reg = <0x48004a10 0x4>;
		ti,bit-shift = <0>;
	};