Fix a typo in the configure script. This get AIX building cleanly.

Submitted by:	Jens-Uwe Mager <jum@helios.de>
Reviewed by:	Aaron Bannert <aaron@clove.org> and Ryan Bloom


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91471 13f79535-47bb-0310-9956-ffa450edef68