Add the options --ipv4, --ipv6 to specify running over ipv4 and/or
ipv6. If neither is specified, then run both.
Signed-off-by: NTanner Love <tannerlove@google.com>
Acked-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>