* NXP PCA954x I2C bus switch

Required Properties:

  - compatible: Must contain one of the following.
    "nxp,pca9540", "nxp,pca9542", "nxp,pca9543", "nxp,pca9544",
    "nxp,pca9545", "nxp,pca9546", "nxp,pca9547", "nxp,pca9548",
    "nxp,pca9646"

  - reg: The I2C address of the device.

  The following required properties are defined externally:

  - Standard I2C mux properties. See i2c-mux.txt in this directory.
  - I2C child bus nodes. See i2c-mux.txt in this directory.

Optional Properties:

  - reset-gpios: Reference to the GPIO connected to the reset input.
  - i2c-mux-idle-disconnect: Boolean; if defined, forces mux to disconnect all
    children in idle state. This is necessary for example, if there are several
    multiplexers on the bus and the devices behind them use same I2C addresses.


Example:

	i2c-switch@74 {
		compatible = "nxp,pca9548";
		#address-cells = <1>;
		#size-cells = <0>;
		reg = <0x74>;

		i2c@2 {
			#address-cells = <1>;
			#size-cells = <0>;
			reg = <2>;

			eeprom@54 {
				compatible = "at,24c08";
				reg = <0x54>;
			};
		};

		i2c@4 {
			#address-cells = <1>;
			#size-cells = <0>;
			reg = <4>;

			rtc@51 {
				compatible = "nxp,pcf8563";
				reg = <0x51>;
			};
		};
	};