* Spreadtrum sound fe driver

This node models spreadtrum sound fe driver

Required properties:

this node allow sound use sound fe dai
- compatible	: "sprd,fe-dai"
- #sound-dai-cells : it used to select cpu dai number,
	if equal 0 means use default dai 0, if equal 1,
	the cpu dai number is determined by the second parameter
	of sound-dai property.

Example:
sprd_fe_dai: sprd-fe-dai {
	compatible = "sprd,fe-dai";
	#sound-dai-cells = <1>;
};

sprd-audio-card,dai-link@1 {
	...
	cpu {
		sound-dai = <&sprd_fe_dai 1>;
	};
	...
};
