ltc2978

Required properties:
- compatible: should contain one of:
  * "lltc,ltc2974"
  * "lltc,ltc2977"
  * "lltc,ltc2978"
  * "lltc,ltc3880"
  * "lltc,ltc3883"
  * "lltc,ltm4676"
- reg: I2C slave address

Optional properties:
- regulators: A node that houses a sub-node for each regulator controlled by
  the device. Each sub-node is identified using the node's name, with valid
  values listed below. The content of each sub-node is defined by the
  standard binding for regulators; see regulator.txt.

Valid names of regulators depend on number of supplies supported per device:
  * ltc2974 : vout0 - vout3
  * ltc2977 : vout0 - vout7
  * ltc2978 : vout0 - vout7
  * ltc3880 : vout0 - vout1
  * ltc3883 : vout0
  * ltm4676 : vout0 - vout1

Example:
ltc2978@5e {
	compatible = "lltc,ltc2978";
	reg = <0x5e>;
	regulators {
		vout0 {
			regulator-name = "FPGA-2.5V";
		};
		vout2 {
			regulator-name = "FPGA-1.5V";
		};
	};
};