Binding for a ST multiplexed clock driver.

This binding supports only simple indexed multiplexers, it does not
support table based parent index to hardware value translations.

This binding uses the common clock binding[1].

[1] Documentation/devicetree/bindings/clock/clock-bindings.txt

Required properties:

- compatible : shall be:
	"st,stih407-clkgen-a9-mux"

- #clock-cells : from common clock binding; shall be set to 0.

- reg : A Base address and length of the register set.

- clocks : from common clock binding

Example:

	clk_m_a9: clk-m-a9@92b0000 {
		#clock-cells = <0>;
		compatible = "st,stih407-clkgen-a9-mux";
		reg = <0x92b0000 0x10000>;

		clocks = <&clockgen_a9_pll 0>,
			 <&clockgen_a9_pll 0>,
			 <&clk_s_c0_flexgen 13>,
			 <&clk_m_a9_ext2f_div2>;
	};
