clk: samsung: Document binding for Exynos4415 clock controller

* Samsung Exynos4415 Clock Controller

The Exynos4415 clock controller generates and supplies clock to various

consumer devices within the Exynos4415 SoC.

Required properties:

- compatible: should be one of the following:

  - "samsung,exynos4415-cmu" - for the main system clocks controller

    (CMU_LEFTBUS, CMU_RIGHTBUS, CMU_TOP, CMU_CPU clock domains).

  - "samsung,exynos4415-cmu-dmc" - for the Exynos4415 SoC DRAM Memory

    Controller (DMC) domain clock controller.

- reg: physical base address of the controller and length of memory mapped

  region.

- #clock-cells: should be 1.

Each clock is assigned an identifier and client nodes can use this identifier

to specify the clock which they consume.

All available clocks are defined as preprocessor macros in

dt-bindings/clock/exynos4415.h header and can be used in device

tree sources.

Example 1: An example of a clock controller node is listed below.

	cmu: clock-controller@10030000 {

		compatible = "samsung,exynos4415-cmu";

		reg = <0x10030000 0x18000>;

		#clock-cells = <1>;

	};

	cmu-dmc: clock-controller@105C0000 {

		compatible = "samsung,exynos4415-cmu-dmc";

		reg = <0x105C0000 0x3000>;

		#clock-cells = <1>;

	};