This driver is implemented to parse the gps_en gpio from device tree
and create a sysfs to control the gpio in gpsd binary. Also it
registers a irq to enable the HW geofencing feature.

SYSFS: This interface is used to toggle gps_en gpio in userspace.

Required Properties:
- compatible: Must be "gps-wake";
- gps-enable-gpio is resource name for gpio which power ON gps

Optional Properties:
- gps-wakeup-gpio is resource name for gps host wake irq line

Example:
gps_wake {
	compatible = "gps-wake";
	id = <0>;
	gps-enable-gpio = <&gpio_i2c_1_20 10 0>;
	gps-wakeup-gpio = <&gpio TEGRA_GPIO(Q, 5) 0>;
	status = "okay";
};