Make make_chaff() static class function to fix spurious clang warning

src/network/transportsender.cc

@@ -260,7 +260,8 @@ void TransportSender<MyState>::rationalize_states( void )
   }
 }
 
-static const string make_chaff( void )
+template <class MyState>
+const string TransportSender<MyState>::make_chaff( void )
 {
   const int CHAFF_MAX = 16;
 

src/network/transportsender.h

@@ -86,6 +86,8 @@ namespace Network {
 
     uint64_t last_heard; /* last time received new state */
 
+    static const string make_chaff( void );
+
   public:
     /* constructor */
     TransportSender( Connection *s_connection, MyState &initial_state );