static constexpr const char file_name[32] is not ok: use string with file name instead

src/alarm-manager.cpp

@@ -40,9 +40,9 @@ Alarmmanager::Alarmmanager(CumbiaPool *cumbia_pool, QWidget *parent) :
 
     CuPluginLoader loader;
     QObject **qo = nullptr;
-    tree_i = loader.get<QuTreeModelPluginInterface>(QuTreeModelPluginInterface::file_name, qo);
+    tree_i = loader.get<QuTreeModelPluginInterface>("libqutreemodel-plugin.so", qo);
     if(!tree_i)
-        perr("%s: plugin \"%s\" not found", __FUNCTION__, QuTreeModelPluginInterface::file_name);
+        perr("%s: plugin \"%s\" not found", __FUNCTION__, "libqutreemodel-plugin.so");
     else {
         QuTreeModelI *mi = tree_i->instantiate({"Alarm"}, this);
         m_model = mi->qmodel();