I2C for Hisilicon hix5hd2 chipset platform

Required properties:
- compatible: Must be "hisilicon,hix5hd2-i2c"
- reg: physical base address of the controller and length of memory mapped
     region.
- interrupts: interrupt number to the cpu.
- #address-cells = <1>;
- #size-cells = <0>;
- clocks: phandles to input clocks.

Optional properties:
- clock-frequency: Desired I2C bus frequency in Hz, otherwise defaults to 100000
- Child nodes conforming to i2c bus binding

Examples:
I2C0@f8b10000 {
	compatible = "hisilicon,hix5hd2-i2c";
	reg = <0xf8b10000 0x1000>;
	interrupts = <0 38 4>;
	clocks = <&clock HIX5HD2_I2C0_RST>;
	#address-cells = <1>;
	#size-cells = <0>;
}
