LINUX: ifconfig's output has changed

net-tools in Fedora 18 has changed 'inet addr' to just 'inet' (possibly
to more closely match the ip command).

Change-Id: I9224d0eb4dd77e248c8f8eed966fa26ec7dda08c
Reviewed-on: http://gerrit.openafs.org/8987
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Marc Dionne <marc.c.dionne@gmail.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>