This fixes the mod_autoindex problem of not getting the list of files.

This fixes the mod_autoindex problem of not getting the list of files.
The problem was that the internal_fast_redirect removed the SUB_REQ
filter, but we are still in a sub_request.  The solution is to have the
fast_internal_Redirect function check if we are in a sub_Request and
re-add the filter if we are.
Submitted by:	Ryan Bloom, Greg Ames, Jeff Trawick, and Will Rowe

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@94456 13f79535-47bb-0310-9956-ffa450edef68