Stop ignoring should_refuse_unknown_exits() for unauthenticated channels
The brackets in this code are wrong in at least two ways:
* they unconditionally reject client channels
* there are two at the start
```
if ((client_chan ||
(!connection_or_digest_is_known_relay(
or_circ->p_chan->identity_digest) &&
should_refuse_unknown_exits(options)))) {
```
Bugfix on d52a1e2 in legacy/trac#22060, note that 66aff2d was merged into that code in 0.3.2.
issue