QtVersion: Allow to clean up autodetected Qt versions

Task-number: QTCREATORBUG-8454

Change-Id: I5e883194abeac84a36523a23c2f588c7c52c1a2a
Reviewed-by: Daniel Teske <daniel.teske@digia.com>

src/plugins/qtsupport/qtoptionspage.cpp

@@ -268,7 +268,7 @@ void QtOptionsPageWidget::cleanUpQtVersions()
 {
     QStringList toRemove;
     foreach (const BaseQtVersion *v, m_versions) {
-        if (!v->isValid() && !v->isAutodetected())
+        if (!v->isValid())
             toRemove.append(v->displayName());
     }