DSO support for NetBSD

Submitted by: Jaromir Dolecek <dolecek@ics.muni.cz>
Reviewed by: Ralf S. Engelschall
PR: 2158


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81069 13f79535-47bb-0310-9956-ffa450edef68