msg/async: do not connect from server

msg/async: do not connect from server

We could have a fault on a server-side of a non-lossy connectoin where
there is a fault and we have outgoing data queued.  Since we are a server,
we cannot connect; we should just go into standby and wait for the other
end to reconnect, or for someone to mark us down.

This fixes a failure reproduced by Messenger/MessengerTest.SyntheticInjectTest/0
where it would assert(!policy.server) in the connect code.

Signed-off-by: Sage Weil <sage@redhat.com>