Driver for the Atmel MACB on-chip ethernet controller.

This driver has been tested on the ATSTK1000 board with a AT32AP7000
CPU. It should probably work on AT91SAM926x as well with some minor
modifications.

Hardware documentation can be found in the AT32AP7000 data sheet,
which can be downloaded from

http://www.atmel.com/dyn/products/datasheets.asp?family_id=682



Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>