Add Failsafe support for Linksys E3000V1 / WRT610NV2

Add Failsafe support for Linksys E3000V1 / WRT610NV2

Adds specification of the correct cpu_port for Linksys E3000V1 and WRT610NV2
in /lib/preinit/05_init_interfaces_brcm.  The list of devices will need to
be expanded.  Is there a way to determine the correct cpu_port to use in a
generic sense; for instance, if "/proc/switch/eth0/port/8" exists, or if
"/sys/class/net/eth0/device/driver/module/drivers/bcma:bgmac" exists?  Could
a similar method be used in "/etc/init.d/netconfig"?

Signed-off-by: Nathan Hintz <nlhintz@hotmail.com>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@35491 3c298f89-4303-0410-b956-a3cf2f4a3e73