Conexant Digicolor SoCs Watchdog timer

The watchdog functionality in Conexant Digicolor SoCs relies on the so called
"Agent Communication" block. This block includes the eight programmable system
timer counters. The first timer (called "Timer A") is the only one that can be
used as watchdog.

Required properties:

- compatible : Should be "cnxt,cx92755-wdt"
- reg : Specifies base physical address and size of the registers
- clocks : phandle; specifies the clock that drives the timer

Optional properties:

- timeout-sec : Contains the watchdog timeout in seconds

Example:

	watchdog@f0000fc0 {
		compatible = "cnxt,cx92755-wdt";
		reg = <0xf0000fc0 0x8>;
		clocks = <&main_clk>;
		timeout-sec = <15>;
	};