Replace a missing line that shutdown a peer that failed comm.

This commit was SVN r23120.

orte/mca/oob/tcp/oob_tcp_peer.c

@@ -596,6 +596,8 @@ void mca_oob_tcp_peer_close(mca_oob_tcp_peer_t* peer)
             peer->peer_state);
     }
 
+    mca_oob_tcp_peer_shutdown(peer);
+
     /* inform the ERRMGR framework that we have lost a connection so
      * it can decide if this is important, what to do about it, etc.
      */