nvmem: rockchip-efuse: describe the usage of eFuse

= Rockchip eFuse device tree bindings =

Required properties:

- compatible: Should be "rockchip,rockchip-efuse"

- reg: Should contain the registers location and exact eFuse size

- clocks: Should be the clock id of eFuse

- clock-names: Should be "pclk_efuse"

= Data cells =

Are child nodes of eFuse, bindings of which as described in

bindings/nvmem/nvmem.txt

Example:

	efuse: efuse@ffb40000 {

		compatible = "rockchip,rockchip-efuse";

		reg = <0xffb40000 0x20>;

		#address-cells = <1>;

		#size-cells = <1>;

		clocks = <&cru PCLK_EFUSE256>;

		clock-names = "pclk_efuse";

		/* Data cells */

		cpu_leakage: cpu_leakage {

			reg = <0x17 0x1>;

		};

	};

= Data consumers =

Are device nodes which consume nvmem data cells.

Example:

	cpu_leakage {

		...

		nvmem-cells = <&cpu_leakage>;

		nvmem-cell-names = "cpu_leakage";

	};