- Defer dellink to net_cleanup() allowing for batching.
- Fix comment.
- Use for_each_netdev_safe again as dev_change_net_namespace touches
  at most one network device (unlike veth dellink).
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>