* RPM Sleep Stats

RPM maintains sleep data in the RPM RAM. A device tree node is added
that will hold the address of the RPM RAM from where sleep stats are read.
Additionally a version number is added to distinguish the type of data
structure being read from the RAM.

The required properties for rpm-stats are:

- compatible: "qcom,rpm-stats"
- reg: The address on the RPM RAM from where stats are read.
- reg-names: Name given the register holding address.
- qcom,sleep-stats-version: Version number.

Example:

qcom,rpm-stats@fc19dbd0 {
		compatible = "qcom,rpm-stats";
		reg = <0xfc19dbd0 0x1000>;
		reg-names = "phys_addr_base";
		qcom,sleep-stats-version = <2>;
};