BCM7038 Watchdog timer

Required properties:

- compatible : should be "brcm,bcm7038-wdt"
- reg : Specifies base physical address and size of the registers.

Optional properties:

- clocks: The clock running the watchdog. If no clock is found the
	  driver will default to 27000000 Hz.

Example:

watchdog@f040a7e8 {
	compatible = "brcm,bcm7038-wdt";
	clocks = <&upg_fixed>;
	reg = <0xf040a7e8 0x16>;
};