Davicom DM9000 Fast Ethernet controller

Required properties:
- compatible = "davicom,dm9000";
- reg : physical addresses and sizes of registers, must contain 2 entries:
    first entry : address register,
    second entry : data register.
- interrupt-parent : interrupt controller to which the device is connected
- interrupts : interrupt specifier specific to interrupt controller

Optional properties:
- local-mac-address : A bytestring of 6 bytes specifying Ethernet MAC address
    to use (from firmware or bootloader)
- davicom,no-eeprom : Configuration EEPROM is not available
- davicom,ext-phy : Use external PHY

Example:

	ethernet@18000000 {
		compatible = "davicom,dm9000";
		reg = <0x18000000 0x2 0x18000004 0x2>;
		interrupt-parent = <&gpn>;
		interrupts = <7 4>;
		local-mac-address = [00 00 de ad be ef];
		davicom,no-eeprom;
	};