Hisilicon BVT I2C master controller

Required properties:
- compatible: should be "hisilicon,hibvt-i2c" and one of the following:
	"hisilicon,hi3516cv300-i2c"
- reg: physical base address of the controller and length of memory mapped.
     region.
- interrupts: interrupt number to the cpu.
- clocks: phandles to input clocks.

Optional properties:
- clock-frequency: Desired I2C bus frequency in Hz, otherwise defaults to 100000.

Other properties:
see Documentation/devicetree/bindings/i2c/i2c.txt.

Examples:
i2c_bus0: i2c@12110000 {
	compatible = "hisilicon,hi3516cv300-i2c", "hisilicon,hibvt-i2c";
	reg = <0x12110000 0x100>;
	interrupts = <20>;
	clocks = <&crg_ctrl HI3516CV300_APB_CLK>;
	clock-frequency = <100000>;
};
