face: delete redundant protocol typedefs.

Change-Id: I32e1100e7395070a29ee813658aac82b63b6c4f2
diff --git a/daemon/face/unix-stream-face.hpp b/daemon/face/unix-stream-face.hpp
index 8492f54..f90a5be 100644
--- a/daemon/face/unix-stream-face.hpp
+++ b/daemon/face/unix-stream-face.hpp
@@ -13,8 +13,7 @@
 #error "Cannot include this file when UNIX sockets are not available"
 #endif
 
-namespace nfd
-{
+namespace nfd {
 
 /**
  * \brief Implementation of Face abstraction that uses stream-oriented
@@ -23,8 +22,6 @@
 class UnixStreamFace : public StreamFace<boost::asio::local::stream_protocol, LocalFace>
 {
 public:
-  typedef boost::asio::local::stream_protocol protocol;
-
   explicit
   UnixStreamFace(const shared_ptr<protocol::socket>& socket);
 };