Make Makefile.nt clean mod_rewrite properly.

PR: 3100
Obtained from:
Submitted by:	Tetsu Maenaka <tetsu-maenaka@usa.net>
Reviewed by:


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@82336 13f79535-47bb-0310-9956-ffa450edef68