Cortina Systems Gemini GPIO Controller

Required properties:

- compatible : Must be "cortina,gemini-gpio"
- reg : Should contain registers location and length
- interrupts : Should contain the interrupt line for the GPIO block
- gpio-controller : marks this as a GPIO controller
- #gpio-cells : Should be 2, see gpio/gpio.txt
- interrupt-controller : marks this as an interrupt controller
- #interrupt-cells : a standard two-cell interrupt flag, see
  interrupt-controller/interrupts.txt

Example:

gpio@4d000000 {
	compatible = "cortina,gemini-gpio";
	reg = <0x4d000000 0x100>;
	interrupts = <22 IRQ_TYPE_LEVEL_HIGH>;
	gpio-controller;
	#gpio-cells = <2>;
	interrupt-controller;
	#interrupt-cells = <2>;
};