build: switch to C++17

Change-Id: Ie68020a04b7e20b74778b6d0370544ded55c5e26
diff --git a/daemon/face/tcp-channel.hpp b/daemon/face/tcp-channel.hpp
index bc6fba4..19c714c 100644
--- a/daemon/face/tcp-channel.hpp
+++ b/daemon/face/tcp-channel.hpp
@@ -31,7 +31,7 @@
 namespace nfd {
 
 namespace tcp {
-typedef boost::asio::ip::tcp::endpoint Endpoint;
+using Endpoint = boost::asio::ip::tcp::endpoint;
 } // namespace tcp
 
 namespace face {