replace use of depreciated QDesktopWidget in GUI * gui-utils.cc: include QApplication, QRect and QScreen; (get_screen_geometry): return QRect with geometry of primary screen; (adjust_to_screen): adjust given QRect to be completely on the screen that contains the largest part of the QRect, use a default geometry if no part is on an available screen * gui-utils.h: include QRect; new function get_screen_geometry and adjust_to_screen * community-news.cc: do not include QDesktopWidget, but gui-utils.h; (get_screen_geometry); move function to gui-utils.cc; * community-news.h: move get_screen_geometry to gui-utils.h * find-dialog.cc: do not include QDesktopWidget, but gui-utils.h; (restore_settings): use new function adjust_to_screen * main-window.cc: do not include QDesktopWidget, but gui-utils.h; (get_screen_geometry: move function to gui-utils.cc * main-window.h: move function get_screen_geometry to gui.utils.h; * octave-dock-widget.cc: do not include QDesktopWidget, but gui-utils.h QScreen and QWindow; (handle_settings): use adjust_to_screen and QGuiApplication->primaryScreen * release-notes.cc: do not include QDesktopWidget, but gui-utils.h and QScreen; (get_screen_geometry): move to gui-utils.cc; * release-notes.h: move get:screen_geometry to gui-utils.h * terminal-dock-widget.cc: do not include QDesktopWidget but QScreen; (terminal_dock_widget): use QGuiApplication->primaryScreen instead of QDesktopWidget->screenGeometry * welcome-wizard.cc: remove include of QDesktopWidget

--- a/libgui/src/terminal-dock-widget.cc	Mon May 16 23:00:27 2022 +0200
+++ b/libgui/src/terminal-dock-widget.cc	Sun Jan 30 16:41:44 2022 +0100
@@ -27,7 +27,7 @@
 #  include "config.h"
 #endif
 
-#include <QDesktopWidget>
+#include <QScreen>
 
 // This header is only needed for the new terminal widget.
 #include "command-widget.h"
@@ -107,8 +107,8 @@
     int win_x =  metrics.maxWidth()*80;
     int win_y =  metrics.height()*25;
 
-    int max_x = QApplication::desktop ()->screenGeometry (this).width ();
-    int max_y = QApplication::desktop ()->screenGeometry (this).height ();
+    int max_x = QGuiApplication::primaryScreen ()->availableGeometry ().width ();
+    int max_y = QGuiApplication::primaryScreen ()->availableGeometry ().height ();
 
     if (win_x > max_x)
       win_x = max_x;