* I2C

Required properties :

 - device_type : Should be "i2c"
 - reg : Offset and length of the register set for the device

Recommended properties :

 - compatible : Should be "fsl-i2c" for parts compatible with
   Freescale I2C specifications.
 - interrupts : <a b> where a is the interrupt number and b is a
   field that represents an encoding of the sense and level
   information for the interrupt.  This should be encoded based on
   the information in section 2) depending on the type of interrupt
   controller you have.
 - interrupt-parent : the phandle for the interrupt controller that
   services interrupts for this device.
 - dfsrr : boolean; if defined, indicates that this I2C device has
   a digital filter sampling rate register
 - fsl5200-clocking : boolean; if defined, indicated that this device
   uses the FSL 5200 clocking mechanism.

Example :
	i2c@3000 {
		interrupt-parent = <40000>;
		interrupts = <1b 3>;
		reg = <3000 18>;
		device_type = "i2c";
		compatible  = "fsl-i2c";
		dfsrr;
	};
