QTI LMH CPU Voltage cooling devices.

The LMH CPU voltage cooling device will be used to place voltage restriction
vote on CPU railway during cold thermal condition. This cooling device driver
will register one cooling device per LLM, which can be used by thermal zone to
place voltage restriction vote.

Properties:
- compatible:
	Usage: required
	Value type: <string>
	Definition: should be "qcom,lmh-cpu-vdd"

Cooling device node:
- reg:
	Usage: Required
	Value type: <a b>
	Definition: where 'a' is the starting register address of the LLM
			and 'b' is the size of LLM address space.

- #cooling-cells:
	Usage: required
	Value type: <integer>
	Definition: Must be 2. Needed for of_thermal as cooling device
			identifier. Please refer to
			<devicetree/bindings/thermal/thermal.txt> for more
			details.
Example:
	lmh_cpu_vdd0: qcom,lmh-cpu-vdd@18350800 {
		compatible = "qcom,lmh-cpu-vdd";
		reg =  <0x18350800 0x1000>;
		#cooling-cells = <2>;
	};