face: configuration option to make UDP multicast face "ad hoc"

Change-Id: Ifd407f42e9646826697f73ab1890c819fce16857
Refs: #4018, #3967
diff --git a/daemon/face/multicast-udp-transport.cpp b/daemon/face/multicast-udp-transport.cpp
index 34bef0c..7b3fca3 100644
--- a/daemon/face/multicast-udp-transport.cpp
+++ b/daemon/face/multicast-udp-transport.cpp
@@ -35,7 +35,8 @@
 MulticastUdpTransport::MulticastUdpTransport(const protocol::endpoint& localEndpoint,
                                              const protocol::endpoint& multicastGroup,
                                              protocol::socket&& recvSocket,
-                                             protocol::socket&& sendSocket)
+                                             protocol::socket&& sendSocket,
+                                             ndn::nfd::LinkType linkType)
   : DatagramTransport(std::move(recvSocket))
   , m_multicastGroup(multicastGroup)
   , m_sendSocket(std::move(sendSocket))
@@ -44,7 +45,7 @@
   this->setRemoteUri(FaceUri(multicastGroup));
   this->setScope(ndn::nfd::FACE_SCOPE_NON_LOCAL);
   this->setPersistency(ndn::nfd::FACE_PERSISTENCY_PERMANENT);
-  this->setLinkType(ndn::nfd::LINK_TYPE_MULTI_ACCESS);
+  this->setLinkType(linkType);
   this->setMtu(udp::computeMtu(localEndpoint));
 
   NFD_LOG_FACE_INFO("Creating transport");