Device-Tree Bindings for a PPS Signal on GPIOThese properties describe a PPS (pulse-per-second) signal connected toa GPIO pin.Required properties:- compatible: should be "pps-gpio"- gpios: one PPS GPIO in the format described by ../gpio/gpio.txtOptional properties:- assert-falling-edge: when present, assert is indicated by a falling edge (instead of by a rising edge)Example: pps {