Fix handling of symlinked pg_stat_tmp and pg_replslot

Magnus Hagander <magnus@hagander.net>

Commit: b6a323a8c9b8f75a974e44cc6bb91f0d08e19e7f
Author: Magnus Hagander <magnus@hagander.net>
Date: 2016-11-07T13:47:30Z
Releases: 9.6.2
Fix handling of symlinked pg_stat_tmp and pg_replslot

This was already fixed in HEAD as part of 6ad8ac60 but was not
backpatched.

Also change the way pg_xlog is handled to be the same as the other
directories.

Patch from me with pg_xlog addition from Michael Paquier, test updates
from David Steele.

Files