Add support for client-cert-not-required for PolarSSL.

Signed-off-by: Tamas TEVESZ <ice@extreme.hu>
Acked-by: Steffan Karger <steffan.karger@fox-it.com>
Message-Id: alpine.GSO.2.03.1306080732510.23277@extreme.hu
URL: http://article.gmane.org/gmane.network.openvpn.devel/7667
Signed-off-by: David Sommerseth <davids@redhat.com>