test prints to debug initial combo model selection

src/i0mapmon_topo.cpp

@@ -111,8 +111,8 @@ void I0mapmon_topo::m_onLabelsReady(const QStringList &names) {
 void I0mapmon_topo::m_onWlenSelectionChanged(QString wlen, bool on) {
     QStringList wlens;
     QVector<int> wlens_idx;
-    for(int i = 1; i < ->rowCount(); i++) { // i = 0 is not checkable
-        QStandardItem *it = ->item(i);
+    for(int i = 1; i < m_cb_model->rowCount(); i++) { // i = 0 is not checkable
+        QStandardItem *it = m_cb_model->item(i);
         if((it->flags() & Qt::ItemIsUserCheckable) &&  it->data(Qt::CheckStateRole).toBool()) {
             wlens.append(it->text());
             wlens_idx << i - 1;