Cosmetically tweak some duplicated code to be even more identical. No
functional change.

* subversion/libsvn_repos/load-fs-vtable.c
  (parse_baton): Rename 'oldest_old_rev' to 'oldest_dumpstream_rev' for
    consistency with svnrdump/load_editor.c, and update all references.
  (adjust_mergeinfo_property): Correct a comment.

* subversion/svnrdump/load_editor.c
  (adjust_mergeinfo_property): New, factored out...
  (set_node_property): ... of here.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1647592 13f79535-47bb-0310-9956-ffa450edef68