CS42888 audio CODEC

This device supports I2C only.

Required properties:

  - compatible: "cirrus,cs42888"
  - reg: the I2C address of the device.
  - clocks: Phandle to the clock node.
  - clock-names: Contains name for each entry in clocks.
		"codec_osc" : the external oscillator.
		"esai" : the hckt clock from esai.
  - <name>-supply: Phandle to the regulator <name>.

Note: cs42888 needs a regulators node and a clocks node.

Example:
In this case, the clock is external oscillator.

codec: cs42888@48 {
	compatible = "cirrus,cs42888";
	reg = <0x048>;
	clocks = <&codec_osc 0>;
	clock-names = "codec_osc";
	VA-supply = <&reg_audio>;
	VD-supply = <&reg_audio>;
	VLS-supply = <&reg_audio>;
	VLC-supply = <&reg_audio>;
};