rds: Fix one-sided connect

rds: Fix one-sided connect

The decision to designate a peer to be the active side did not take
loopback connections into account. Further, a bug in
rds_shutdown_worker where the passive side, in case of no reconnect
racing, did not attempt to restart the connection.

Orabug: 29391909

Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Tested-by: Rosa Lopez <rosa.lopez@oracle.com>
Reviewed-by: Dag Moxnes <dag.moxnes@oracle.com>
---

v1 -> v2:
   * Incorporated review comments from Dag
   * Split the commit in two

Signed-off-by: Brian Maly <brian.maly@oracle.com>