Improved compilation and DSO support on Sequent DYNIX/ptx.

PR: 4735
Submitted by:	Ian Turner <iant@sequent.com>
Reviewed by:	Roy Fielding


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@83620 13f79535-47bb-0310-9956-ffa450edef68