We only really need to call shutdown() if we're in the ESTABLISHED TCP
state, since that is the only case where the client is initiating a
close of an established connection.
If the socket is in FIN_WAIT1 or FIN_WAIT2, then we've already initiated
socket shutdown and are waiting for the server's reply, so do nothing.
In all other cases where we've already received a FIN from the server,
we should be able to just close the socket.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>