fixed compile errors in Release mode

shadowsocks-csharp/Controller/Logging.cs

@@ -48,9 +48,9 @@ namespace Shadowsocks.Controller
 #endif
         }
 
-#if DEBUG
         public static void Debug(EndPoint local, EndPoint remote, int len, string header = null, string tailer = null)
         {
+#if DEBUG
             if (header == null && tailer == null)
                 Debug($"{local} => {remote} (size={len})");
             else if (header == null && tailer != null)
@@ -59,13 +59,15 @@ namespace Shadowsocks.Controller
                 Debug($"{header}: {local} => {remote} (size={len})");
             else
                 Debug($"{header}: {local} => {remote} (size={len}), {tailer}");
+#endif
         }
 
         public static void Debug(Socket sock, int len, string header = null, string tailer = null)
         {
+#if DEBUG
             Debug(sock.LocalEndPoint, sock.RemoteEndPoint, len, header, tailer);
-        }
 #endif
+        }
 
         public static void LogUsefulException(Exception e)
         {