Update installation instructions to reflect the fact that in-tree libs
fetched by get-deps.sh no longer are configured and built automatically.

* INSTALL (Dependencies in Detail): Update text about libs retrieved
   by get-deps.sh.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1467668 13f79535-47bb-0310-9956-ffa450edef68