To do so we do a quick setns into the container's netns.  This
(unexpectedly) turns out cleaner than trying to rename it from
lxc_setup(), because we don't know the original nic name in
the container until we created it which we do in the parent
after the init has been cloned.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>