Canonicalize when svnserve.conf has a URL as the authz-db config setting.

* subversion/svnserve/serve.c
  (load_authz_config): URLs should have been canonical.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1429135 13f79535-47bb-0310-9956-ffa450edef68