ARM: bcm2835: dt: Add the ethernet to the device trees

The hub and the ethernet in its port 1 are hardwired on the board.

Compared to the adapters that can be plugged into the USB ports, this
one has no serial EEPROM to store its MAC. Nevertheless, the Raspberry Pi
has the MAC address for this adapter in its ROM, accessible from its
firmware.

U-Boot can read out the address and set the local-mac-address property of the
node with "ethernet" alias. Let's add the node so that U-Boot can do its
business.

Model B rev2 and Model B+ entries were verified by me, the hierarchy and
pid/vid pair for the Version 2 was provided by Peter Chen. Original
Model B is a blind shot, though very likely correct.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Eric Anholt <eric@anholt.net>