Fixed misleading message.

src/maxwell_interface.cpp

@@ -596,8 +596,11 @@ parameter_loader::postpro_fieldExportMode(const std::string& field) const
     if (silo_mode == "zonal")
         return field_export_mode::ZONAL;
 
-    std::cout << "[CONFIG] warning: invalid export mode '" << silo_mode;
-    std::cout << "'" << std::endl;
+    if (silo_mode != "none")
+    {
+        std::cout << "[CONFIG] warning: invalid export mode '" << silo_mode;
+        std::cout << "'" << std::endl;
+    }
 
     return field_export_mode::NONE;
 }