face: allow setting default UDP face MTU in config

refs #5138

Change-Id: Ibb3767b27aec2b046d1f41292f3d61001866f8c0
diff --git a/tests/other/face-benchmark.cpp b/tests/other/face-benchmark.cpp
index 9ee179f..28af8dc 100644
--- a/tests/other/face-benchmark.cpp
+++ b/tests/other/face-benchmark.cpp
@@ -47,7 +47,7 @@
     : m_terminationSignalSet{getGlobalIoService()}
     , m_tcpChannel{tcp::Endpoint{boost::asio::ip::tcp::v4(), 6363}, false,
                    bind([] { return ndn::nfd::FACE_SCOPE_NON_LOCAL; })}
-    , m_udpChannel{udp::Endpoint{boost::asio::ip::udp::v4(), 6363}, 10_min, false}
+    , m_udpChannel{udp::Endpoint{boost::asio::ip::udp::v4(), 6363}, 10_min, false, ndn::MAX_NDN_PACKET_SIZE}
   {
     m_terminationSignalSet.add(SIGINT);
     m_terminationSignalSet.add(SIGTERM);