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

Change-Id: Ieb6df864ab82f77b2bee9e83aa0bfa2005715950
Refs: #3857
diff --git a/src/mgmt/nfd/control-parameters.hpp b/src/mgmt/nfd/control-parameters.hpp
index d57c75d..a798459 100644
--- a/src/mgmt/nfd/control-parameters.hpp
+++ b/src/mgmt/nfd/control-parameters.hpp
@@ -99,10 +99,10 @@
   size_t
   wireEncode(EncodingImpl<TAG>& encoder) const;
 
-  virtual Block
+  Block
   wireEncode() const final;
 
-  virtual void
+  void
   wireDecode(const Block& wire) final;
 
 public: // getters & setters