* Prevent r->parsed_uri.path from being NULL as this can cause segmentation

  faults e.g. in mod_cache. Set it to "/" in this case.

PR: 39259
Submitted by: Davi Arnaut <davi haxent.com.br>
Reviewed by: rpluem


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@393037 13f79535-47bb-0310-9956-ffa450edef68