Define a new vendor property in the maxim,max9286 binding schema.
The new property allows to declare that the remote camera
power-over-coax is controlled by one of the MAX9286 gpio lines.
As it is currently not possible to establish a regulator as consumer
of the MAX9286 gpio controller for this purpose, the property allows to
declare that the camera power is controlled by the MAX9286 directly.
The property accepts a gpio-index (0 or 1) and one line polarity
flag as defined by dt-bindings/gpio/gpio.h.