Update Configure script to allow building Apache on IBM's IA64 version of AIX.

Submitted by:  Paul Reder
Reviewed by:  Bill Stoddard


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@86217 13f79535-47bb-0310-9956-ffa450edef68