MIPS: Octeon: device_tree_init: use separate pass to fill mac addresses

Use separate pass to fill MAC addresses. This is needed because we want
to do this also for the appended DTB.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/12588/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>