* Renesas R-Car GPIO Controller

Required Properties:

  - compatible: should be one of the following.
    - "renesas,gpio-r8a7778": for R8A7778 (R-Mobile M1) compatible GPIO controller.
    - "renesas,gpio-r8a7779": for R8A7779 (R-Car H1) compatible GPIO controller.
    - "renesas,gpio-r8a7790": for R8A7790 (R-Car H2) compatible GPIO controller.
    - "renesas,gpio-rcar": for generic R-Car GPIO controller.

  - reg: Base address and length of each memory resource used by the GPIO
    controller hardware module.

  - interrupt-parent: phandle of the parent interrupt controller.
  - interrupts: Interrupt specifier for the controllers interrupt.

  - gpio-controller: Marks the device node as a gpio controller.
  - #gpio-cells: Should be 2. The first cell is the GPIO number and the second
    cell specifies GPIO flags, as defined in <dt-bindings/gpio/gpio.h>. Only the
    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
  - gpio-ranges: Range of pins managed by the GPIO controller.

Please refer to gpio.txt in this directory for details of gpio-ranges property
and the common GPIO bindings used by client devices.

Example: R8A7779 (R-Car H1) GPIO controller nodes

	gpio0: gpio@ffc40000 {
		compatible = "renesas,gpio-r8a7779", "renesas,gpio-rcar";
		reg = <0xffc40000 0x2c>;
		interrupt-parent = <&gic>;
		interrupts = <0 141 0x4>;
		#gpio-cells = <2>;
		gpio-controller;
		gpio-ranges = <&pfc 0 0 32>;
	};
	...
	gpio6: gpio@ffc46000 {
		compatible = "renesas,gpio-r8a7779", "renesas,gpio-rcar";
		reg = <0xffc46000 0x2c>;
		interrupt-parent = <&gic>;
		interrupts = <0 147 0x4>;
		#gpio-cells = <2>;
		gpio-controller;
		gpio-ranges = <&pfc 0 192 9>;
	};
