Fix another #ifdef/#if P2MP_SERVER

Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <1370013992-18592-1-git-send-email-arne@rfc2549.org>
URL: http://article.gmane.org/gmane.network.openvpn.devel/7647

Signed-off-by: Gert Doering <gert@greenie.muc.de>