Now that it is finally possible to get the MAC addresses from the OTP
memory, use it to set the addresses of the network devices.

There are 8 reserved MAC addresses in total per board. Distribute them
as follows:

+----------+------+------+------+------+------+
|          | var1 | var2 | var3 | var4 | kbox |
+----------+------+------+------+------+------+
| enetc #0 |   +0 |      |      |   +0 |   +0 |
| enetc #1 |      |      |   +0 |   +1 |   +1 |
| enetc #2 |      |   +2 |      |      |   +2 |
| enetc #3 |      |   +3 |      |      |   +3 |
| felix p0 |      |   +0 |      |      |   +4 |
| felix p1 |      |   +1 |      |      |   +5 |
| felix p2 |      |      |      |      |   +6 |
| felix p3 |      |      |      |      |   +7 |
| felix p4 |      |      |      |      |      |
| felix p5 |      |      |      |      |      |
+----------+------+------+------+------+------+

An empty cell means, the port is not available and thus doesn't need an
ethernet address.
Signed-off-by: Michael Walle <michael@walle.cc>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>