ROCKCHIP multicodecs audio

Required properties:
- compatible: "rockchip,multicodecs-card"
- rockchip,cpu: The phandle of the Rockchip I2S/PDM controller that's
  connected to the CODEC
- rockchip,codec: The phandle of audio codecs

Optional properties:
- rockchip,card-name: User specified audio sound card name, one string property.
- rockchip,codec-hp-det : Detect the headphone via internal codec.
- rockchip,wait-card-locked : This is a variable length array, user specified
			      these sound cards need to be prepared and locked,
			      otherwise the local slave card can be probed.

Optional dai-link subnode properties:
- rockchip,format			: CPU/CODEC common audio format.
					  "i2s", "right_j", "left_j" , "dsp_a"
					  "dsp_b", "ac97", "pdm", "msb", "lsb".
- rockchip,frame-master			: Indicates dai-link frame master.
					  phandle to a cpu or codec subnode.
- rockchip,bitclock-master		: Indicates dai-link bit clock master.
					  phandle to a cpu or codec subnode.
- rockchip,bitclock-inversion		: bool property. Add this if the
					  dai-link uses bit clock inversion.
- rockchip,frame-inversion		: bool property. Add this if the
					  dai-link uses frame clock inversion.
- rockchip,mclk-fs     			: Multiplication factor between stream
					  rate and codec mclk, applied only for
					  the dai-link.

Example:

sound {
	compatible = "rockchip,multicodecs-card";
	rockchip,mclk-fs = <256>;
	rockchip,cpu = <&i2s0_8ch>;
	rockchip,codec = <&codec>, <&vad>;
};