net: tcp: Allow immediate connection tear down

If the network interface goes down, then we do not have any time
to tear down TCP connection gracefully because there is no more
a connection to send data to. In this case the TCP connection is
forcefully closed without going into FIN_WAIT_1 state.

Signed-off-by: Jukka Rissanen <jukka.rissanen@nordicsemi.no>
3 files changed