Handle netdev secondary addresses and labels

Handle netdev secondary addresses and labels

Fix the network-bridge logic to correctly transfer secondary IP
address from $netdev to $bridge.

e.g. if you add an secondary address/label/alias with:

  $> ip addr add 172.31.0.200/24 dev eth0 label eth0:00

then, "ip addr show dev eth0" gives e.g.:

  inet 172.31.0.10/24 brd 172.31.0.255 scope global eth0
  inet 172.31.0.200/24 scope global secondary eth0:00

and transfer_addrs() tries to execute:

  ip addr add 172.31.0.10/24 brd 172.31.0.255 scope global dev tmpbridge
  ip addr add 172.31.0.200/24 scope global secondary dev tmpbridge:00

which causes the sript to fail because:

  1) The device tmpbridge:00 doesn't exist
  2) The "secondary" flag isn't valid

This patch fixes the sed commands to instead give:

  ip addr add 172.31.0.10/24 brd 172.31.0.255 scope global dev tmpbridge label tmpbridge
  ip addr add 172.31.0.200/24 scope global dev tmpbridge label tmpbridge:00

Signed-off-by: Mark McLoughlin <markmc@redhat.com>