nvmet-tcp: fix unhandled tcp states in nvmet_tcp_state_change()

TCP_FIN_WAIT2 and TCP_LAST_ACK were not handled, the connection is closing
so we can ignore them and avoid printing the "unhandled state"
warning message.

[ 1298.852386] nvmet_tcp: queue 2 unhandled state 5
[ 1298.879112] nvmet_tcp: queue 7 unhandled state 5
[ 1298.884253] nvmet_tcp: queue 8 unhandled state 5
[ 1298.889475] nvmet_tcp: queue 9 unhandled state 5

v2: Do not call nvmet_tcp_schedule_release_queue(), just ignore
the fin_wait2 and last_ack states.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/tcp.c

@@ -1506,6 +1506,9 @@ static void nvmet_tcp_state_change(struct sock *sk)
 		goto done;
 
 	switch (sk->sk_state) {
+	case TCP_FIN_WAIT2:
+	case TCP_LAST_ACK:
+		break;
 	case TCP_FIN_WAIT1:
 	case TCP_CLOSE_WAIT:
 	case TCP_CLOSE: