Binding for the LTC2952 PowerPath controller

This chip is used to externally trigger a system shut down. Once the trigger has
been sent, the chips' watchdog has to be reset to gracefully shut down.
If the Linux systems decides to shut down it powers off the platform via the
kill signal.

Required properties:

- compatible:		Must contain: "lltc,ltc2952"
- trigger-gpios:	phandle + gpio-specifier for the GPIO connected to the
			chip's trigger line
- watchdog-gpios:	phandle + gpio-specifier for the GPIO connected to the
			chip's watchdog line
- kill-gpios:		phandle + gpio-specifier for the GPIO connected to the
			chip's kill line

Example:

ltc2952 {
	compatible = "lltc,ltc2952";

	trigger-gpios = <&gpio0 1 GPIO_ACTIVE_LOW>;
	watchdog-gpios = <&gpio1 2 GPIO_ACTIVE_HIGH>;
	kill-gpios = <&gpio0 2 GPIO_ACTIVE_LOW>;
};
