Verify that package dhparam is required
Package dhparam might not be required. The only dependency is foris-controller-openvpn-plugin but core package for openvpn
turris-cagen does not depend on it.
turris-cagen also seems to generate dhparam itself. It seems that turris-cagen just does that for itself and it might not be required at all in the end.
Please @jschlehofer investigate.