[libcalamares] Reduce object churn

- we don't need to allocate a new translator each time the language changes

src/libcalamares/utils/Retranslator.cpp

@@ -167,19 +167,19 @@ TZLoader::tryLoad( QTranslator* translator )
 
 static void
 loadSingletonTranslator( TranslationLoader&& loader, QTranslator*& translator_p )
+{
+    if ( !translator_p )
     {
         QTranslator* translator = new QTranslator();
         loader.tryLoad( translator );
-
-    if ( translator_p )
-    {
-        QCoreApplication::removeTranslator( translator_p );
-        delete translator_p;
-    }
-
         QCoreApplication::installTranslator( translator );
         translator_p = translator;
     }
+    else
+    {
+        loader.tryLoad( translator_p );
+    }
+}
 
 namespace CalamaresUtils
 {