BCM6368 Random number generator

Required properties:

- compatible : should be "brcm,bcm6368-rng"
- reg : Specifies base physical address and size of the registers
- clocks : phandle to clock-controller plus clock-specifier pair
- clock-names : "ipsec" as a clock name

Example:
	random: rng@10004180 {
		compatible = "brcm,bcm6368-rng";
		reg = <0x10004180 0x14>;

		clocks = <&periph_clk 18>;
		clock-names = "ipsec";
	};
