Fix regression from r6383 that broke decode rest in directory

git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/wsjtx@6390 ab8295b8-cf94-4d9e-aec4-7959e3be5d79

mainwindow.cpp

@@ -1640,6 +1640,7 @@ void MainWindow::on_actionOpen_next_in_directory_triggered()   //Open Next
       tx_status_label->setText(" " + baseName + " ");
       m_diskData=true;
       read_wav_file (fname);
+      return;
     }
   }
 }