Fixes the build of proxy on Windows. Since the proxy_module is declared

as extern using AP_MODULE_DECLARE_DATA that expands to dllexport, there
is a LNK2001 error when building proxy_http.
PR:
Obtained from:		Mladen Turk <mturk@apache.org>
Submitted by:
Reviewed by:


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@104469 13f79535-47bb-0310-9956-ffa450edef68