*8994 CPU LDO Retention Voltage Configuration

This device is used to program the appropriate LDO voltage for 8994 target
from the pre-programmed register.

Required properties:
- compatible:
		Must be "qcom,8994-cpu-ldo-vref"
- reg:
		The register holds the base address to LDO_BHS. Use this
		register base to configure the LDO for all the cpus.
- qcom,ldo-vref-ret:
		Value to which the ldo voltage reference needs to be
		programmed.
		Value to be used is encoded. 0x20 = 0.5V and 0x2a = 0x55V

Example:
	ldo0:ldo-vref@f9070000 {
		compatible = "qcom,8994-cpu-ldo-vref";
		reg = <0xf9070000 0x30>,
		qcom,ldo-vref-ret = <0x20>;
	};
