MSM GPIO controller bindings

Required properties:
- compatible:
  - "qcom,msm-gpio" for MSM controllers
- #gpio-cells : Should be two.
  - first cell is the pin number
  - second cell is used to specify optional parameters (unused)
- gpio-controller : Marks the device node as a GPIO controller.
- #interrupt-cells : Should be 2.
- interrupt-controller: Mark the device node as an interrupt controller
- interrupts : Specify the TLMM summary interrupt number
- ngpio : Specify the number of MSM GPIOs

Example:

	msmgpio: gpio@fd510000 {
		compatible = "qcom,msm-gpio";
		gpio-controller;
		#gpio-cells = <2>;
		interrupt-controller;
		#interrupt-cells = <2>;
		reg = <0xfd510000 0x4000>;
		interrupts = <0 208 0>;
		ngpio = <150>;
	};
