mod_cgi[d]: Close the connection after handling nph- scripts.

mod_cgi[d]: Close the connection after handling nph- scripts.

The HTTP output filters chain is bypassed for nph- scripts (whatever this
means), so there is no way to know whether the connection is reusable after
sending the cgi response (opaque header + body).

Set r->connection->keepalive = AP_CONN_CLOSE unconditionally.

For instance test frameork's "nph-foldhdr.pl" script responds with HTTP/1.0
and no Content-Length so closing the connection is the only way to detect the
end of response for the peer.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1897563 13f79535-47bb-0310-9956-ffa450edef68