Synopsys Designware Watchdog Timer

Required Properties:

- compatible	: Should contain "snps,dw-wdt"
- reg		: Base address and size of the watchdog timer registers.
- clocks	: phandle + clock-specifier for the clock that drives the
		watchdog timer.

Optional Properties:

- interrupts	: The interrupt used for the watchdog timeout warning.
- resets	: phandle pointing to the system reset controller with
		line index for the watchdog.

Example:

	watchdog0: wd@ffd02000 {
		compatible = "snps,dw-wdt";
		reg = <0xffd02000 0x1000>;
		interrupts = <0 171 4>;
		clocks = <&per_base_clk>;
		resets = <&rst WDT0_RESET>;
	};