[Qt] use tr() instead of QObject::tr() in intro.cpp

src/qt/intro.cpp

@@ -181,8 +181,8 @@ void Intro::pickDataDirectory(bool fIsTestnet)
                 fs::create_directory(dataDir.toStdString());
                 break;
             } catch(fs::filesystem_error &e) {
-                QMessageBox::critical(0, QObject::tr("Bitcoin"),
-                                      QObject::tr("Error: Specified data directory \"%1\" can not be created.").arg(dataDir));
+                QMessageBox::critical(0, tr("Bitcoin"),
+                    tr("Error: Specified data directory \"%1\" can not be created.").arg(dataDir));
                 /* fall through, back to choosing screen */
             }
         }