When relying on x.509 certs for auth and / or encryption of traffic you can't
use package openvpn-nossl.
Just have your package depend on openvpn-crypto to have SSL-encryption and
X.509-support enabled in OpenVPN. If encryption / X.509 is not a must, use
virtual packge openvpn, which is provided by all OpenVPN-variants.
Signed-off-by: Sven Roederer <devel-sven@geroedel.de>