VIA VT8500 and Wondermedia WM8xxx-series pinmux/gpio controller

These SoCs contain a combined Pinmux/GPIO module. Each pin may operate as
either a GPIO in, GPIO out or as an alternate function (I2C, SPI etc).

Required properties:
- compatible: "via,vt8500-pinctrl", "wm,wm8505-pinctrl", "wm,wm8650-pinctrl",
	"wm8750-pinctrl" or "wm,wm8850-pinctrl"
- reg: Should contain the physical address of the module's registers.
- interrupt-controller: Marks the device node as an interrupt controller.
- #interrupt-cells: Should be two.
- gpio-controller: Marks the device node as a GPIO controller.
- #gpio-cells : Should be two. The first cell is the pin number and the
  second cell is used to specify optional parameters.
	bit 0 - active low

Please refer to ../gpio/gpio.txt for a general description of GPIO bindings.

Please refer to pinctrl-bindings.txt in this directory for details of the
common pinctrl bindings used by client devices, including the meaning of the
phrase "pin configuration node".

Each pin configuration node lists the pin(s) to which it applies, and one or
more of the mux functions to select on those pin(s), and pull-up/down
configuration. Each subnode only affects those parameters that are explicitly
listed. In other words, a subnode that lists only a mux function implies no
information about any pull configuration. Similarly, a subnode that lists only
a pull parameter implies no information about the mux function.

Required subnode-properties:
- wm,pins: An array of cells. Each cell contains the ID of a pin.

Optional subnode-properties:
- wm,function: Integer, containing the function to mux to the pin(s):
  0: GPIO in
  1: GPIO out
  2: alternate

- wm,pull: Integer, representing the pull-down/up to apply to the pin(s):
  0: none
  1: down
  2: up

Each of wm,function and wm,pull may contain either a single value which
will be applied to all pins in wm,pins, or one value for each entry in
wm,pins.

Example:

	pinctrl: pinctrl {
		compatible = "wm,wm8505-pinctrl";
		reg = <0xD8110000 0x10000>;
		interrupt-controller;
		#interrupt-cells = <2>;
		gpio-controller;
		#gpio-cells = <2>;
	};
