* palmas device tree bindings

The TI palmas family current members :-
twl6035 (palmas)
twl6037 (palmas)
tps65913 (palmas)
tps65914 (palmas)

Required properties:
- compatible : Should be from the list
  ti,twl6035
  ti,twl6036
  ti,twl6037
  ti,tps65913
  ti,tps65914
  ti,tps80036
and also the generic series names
  ti,palmas
- interrupt-controller : palmas has its own internal IRQs
- #interrupt-cells : should be set to 2 for IRQ number and flags
  The first cell is the IRQ number.
  The second cell is the flags, encoded as the trigger masks from
  Documentation/devicetree/bindings/interrupts.txt
- interrupt-parent : The parent interrupt controller.

Optional properties:
  ti,mux-padX : set the pad register X (1-2) to the correct muxing for the
		hardware, if not set will use muxing in OTP.

Example:

palmas {
	compatible = "ti,twl6035", "ti,palmas";
	reg = <0x48>
	interrupt-parent = <&intc>;
	interrupt-controller;
	#interrupt-cells = <2>;

	ti,mux-pad1 = <0>;
	ti,mux-pad2 = <0>;

	#address-cells = <1>;
	#size-cells = <0>;

	pmic {
		compatible = "ti,twl6035-pmic", "ti,palmas-pmic";
		....
	};
}