[ARM] 4886/1: Orion: grab ts209 ethernet MAC address from flash

[ARM] 4886/1: Orion: grab ts209 ethernet MAC address from flash

The bootloader on ts209 Orion boards doesn't configure the right
ethernet MAC address into the GigE unit on boot.  The only way to
get the MAC address is by parsing it from the 'NAS Config' flash
partition, which is an ext2 partition that contains a file which
holds the MAC address in plain text (format "xx:xx:xx:xx:xx:xx\n")
-- this patch does that.

Tested-by: Martin Michlmayr <tbm@cyrius.com>
Cc: Byron Bradley <byron.bbradley@gmail.com>
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>