src: drop 'virtual' from functions marked 'final' or 'override'

Change-Id: Ieb6df864ab82f77b2bee9e83aa0bfa2005715950
Refs: #3857
diff --git a/src/transport/tcp-transport.hpp b/src/transport/tcp-transport.hpp
index eb7878b..57004bc 100644
--- a/src/transport/tcp-transport.hpp
+++ b/src/transport/tcp-transport.hpp
@@ -49,25 +49,25 @@
   explicit
   TcpTransport(const std::string& host, const std::string& port = "6363");
 
-  ~TcpTransport();
+  ~TcpTransport() override;
 
-  virtual void
+  void
   connect(boost::asio::io_service& ioService,
           const ReceiveCallback& receiveCallback) override;
 
-  virtual void
+  void
   close() override;
 
-  virtual void
+  void
   pause() override;
 
-  virtual void
+  void
   resume() override;
 
-  virtual void
+  void
   send(const Block& wire) override;
 
-  virtual void
+  void
   send(const Block& header, const Block& payload) override;
 
   /** \brief Create transport with parameters defined in URI