Freescale i.MX audio complex with Cadence HDMI

Required properties:
- compatible : "fsl,imx-audio-cdnhdmi"
- model : The user-visible name of this sound complex
- audio-cpu : The phandle of the i.MX SAI controller
- protocol : 0 is hdmi,  1 is dp.

Example:

sound-hdmi {
	compatible = "fsl,imx-audio-cdnhdmi";
	model = "imx-audio-hdmi";
	audio-cpu = <&sai4>;
	protocol = <0>;
};