fixed more "statement has no effect" warnings

src/commands/LoadCommands.cpp

@@ -271,7 +271,7 @@ unsigned BuiltinCommandsModule::DiscoverPluginsAtPath(
 bool BuiltinCommandsModule::IsPluginValid(const wxString & path, bool bFast)
 {
    // bFast is unused as checking in the list is fast.
-   bFast;
+   static_cast<void>(bFast); // avoid unused variable warning
    return mNames.Index(path) != wxNOT_FOUND;
 }