Device tree configuration for the I2C Interrupt Controller on the AST24XX and
AST25XX SoCs.

Required Properties:
- #address-cells	: should be 1
- #size-cells 		: should be 1
- #interrupt-cells 	: should be 1
- compatible 		: should be "aspeed,ast2400-i2c-ic"
			  or "aspeed,ast2500-i2c-ic"
- reg			: address start and range of controller
- interrupts		: interrupt number
- interrupt-controller	: denotes that the controller receives and fires
			  new interrupts for child busses

Example:

i2c_ic: interrupt-controller@0 {
	#address-cells = <1>;
	#size-cells = <1>;
	#interrupt-cells = <1>;
	compatible = "aspeed,ast2400-i2c-ic";
	reg = <0x0 0x40>;
	interrupts = <12>;
	interrupt-controller;
};
