dhclient: add support for FIB

[manu]

Looks ok and fib 0 won't break.

[tsoome]

sbin/dhclient/dhclient-script

25

As discussed on IRC; route command already is picking this value as default; this suggests the ifconfig should do the same for consistent behavior. So, while this change does indeed fix the fib value use case, the proper fix (IMO) would be to fix ifconfig, and then this patch would not be needed.

[bapt]

In fact this change does not make sense, to be able to have dhclient properly set the routing table in the right fib, the way to do it is the following: 1. tag your iface: ifconfig $iface fib X, 2/ run dhclient in the right fib: setfib X $iface and that's all, route if fib aware already, and ifconfig is also fib aware as long as the fib is already set on the iface.