Allow mod_so to be enabled by default even if no shared libraries from the

Allow mod_so to be enabled by default even if no shared libraries from the
core are requested.

If you want to disable shared library support, pass --disable-so to
configure (as always).  This will enforce that your httpd can NOT use
shared libraries - which may be a good thing for you to do.

Justin added the APR_HAS_DSO check per discussion on-list between Aaron,
Ryan, Greg, and the rest of the peanut gallery.  This should allow us
to not build mod_so when it isn't supported.  However, the rest of the
configure scripts need to know that shared objects aren't supported and
complain accordingly.  (sharedobjs = yes, error out?)

Submitted by:	Aaron Bannert <aaron@clove.org>
Reviewed by:	Justin Erenkrantz

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@91393 13f79535-47bb-0310-9956-ffa450edef68