demo_interface_service_vni: Add find_linecard check
demo_interface_service_vni: Add find_linecard check

cisco/cisco-network-puppet-module,cisco/cisco-network-puppet-module,cisco/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module,cisco/cisco-network-puppet-module,mikewiebe/cisco-network-puppet-module