Freescale i.MX audio complex with CS42888 codec

Required properties:
- compatible : "fsl,imx-audio-cs42888"
- model : The user-visible name of this sound complex
- esai-controller : The phandle of the i.MX SSI controller
- audio-codec : The phandle of the CS42888 audio codec

Optional properties:
- asrc-controller : The phandle of the i.MX ASRC controller
- audio-routing : A list of the connections between audio components.
  Each entry is a pair of strings, the first being the connection's sink,
  the second being the connection's source. Valid names could be power
  supplies, CS42888 pins, and the jacks on the board:

Example:

sound {
	compatible = "fsl,imx6q-sabresd-wm8962",
		     "fsl,imx-audio-wm8962";
	model = "cs42888-audio";
	esai-controller = <&esai>;
	asrc-controller = <&asrc_p2p>;
	audio-codec = <&codec>;
};