[media] dt: binding: add binding for ImgTec IR block

* ImgTec Infrared (IR) decoder version 1

This binding is for Imagination Technologies' Infrared decoder block,

specifically major revision 1.

Required properties:

- compatible:		Should be "img,ir-rev1"

- reg:			Physical base address of the controller and length of

			memory mapped region.

- interrupts:		The interrupt specifier to the cpu.

Optional properties:

- clocks:		List of clock specifiers as described in standard

			clock bindings.

			Up to 3 clocks may be specified in the following order:

			1st:	Core clock (defaults to 32.768KHz if omitted).

			2nd:	System side (fast) clock.

			3rd:	Power modulation clock.

- clock-names:		List of clock names corresponding to the clocks

			specified in the clocks property.

			Accepted clock names are:

			"core":	Core clock.

			"sys":	System clock.

			"mod":	Power modulation clock.

Example:

	ir@02006200 {

		compatible = "img,ir-rev1";

		reg = <0x02006200 0x100>;

		interrupts = <29 4>;

		clocks = <&clk_32khz>;

		clock-names =  "core";

	};