Fix a small memory leak when resolving PTR addresses

Fixes bug 11437; bugfix on 0.2.4.7-alpha.

Found by coverity; this is CID 1198198.
Merge remote-tracking branch 'public/bug11437_024' into maint-0.2.4
Merge remote-tracking branch 'origin/maint-0.2.4'
Start work on the changelog for 0.2.5.4-alpha

This commit does nothing other than pull the changes/* files into
ChangeLog, sorted by declared type.  I haven't comined any entries or
vetted anything yet.