Fix problem with error from hp/ux make when no modules in modules/ dir.

Submitted by:	Marc Slemko
Reviewed by:	Dean Gaudet, Alexei Kosut


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@78455 13f79535-47bb-0310-9956-ffa450edef68