conntrack: Fix TCP conntrack state

If a TCP connection is in SYN_SENT state, receiving another SYN packet
would just renew the timeout of that conntrack entry rather than create
a new one.  Thus, tcp_conn_update() should return CT_UPDATE_VALID_NEW.

This also fixes regressions of a couple of  OVN system tests.

Fixes: a867c01 ("conntrack: Fix conntrack new state")
Reported-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: Yi-Hung Wei <yihung.wei@gmail.com>
Tested-by: Dumitru Ceara <dceara@redhat.com>
Signed-off-by: William Tu <u9012063@gmail.com>

lib/conntrack-tcp.c

@@ -189,7 +189,7 @@ tcp_conn_update(struct conntrack *ct, struct conn *conn_,
         } else if (src->state <= CT_DPIF_TCPS_SYN_SENT) {
             src->state = CT_DPIF_TCPS_SYN_SENT;
             conn_update_expiration(ct, &conn->up, CT_TM_TCP_FIRST_PACKET, now);
-            return CT_UPDATE_NEW;
+            return CT_UPDATE_VALID_NEW;
         }
     }