Aspeed Watchdog Timer

Required properties:
 - compatible: must be one of:
	- "aspeed,ast2400-wdt"
	- "aspeed,ast2500-wdt"

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

Example:

	wdt1: watchdog@1e785000 {
		compatible = "aspeed,ast2400-wdt";
		reg = <0x1e785000 0x1c>;
	};
