Exit menu: restore long-press to exit directly (#10000)

Unwillingly removed by 8ef426d79.

frontend/ui/elements/common_exit_menu_table.lua

@@ -7,6 +7,9 @@ local exit_settings = {}
 
 exit_settings.exit_menu = {
     text = _("Exit"),
+    hold_callback = function()
+        UIManager:broadcastEvent(Event:new("Exit"))
+    end,
     -- submenu entries will be appended by xyz_menu_order_lua
 }
 exit_settings.exit = {