Add about command to menu and restructure code. Delete preliminary code from mainloop. Better code will follow

stm-firmware/ui/menu.c

@@ -174,6 +174,24 @@ void menu_list_scroll_down(struct menu_list *list)
 	}
 }
 
+void menu_list_enter_selected_entry(struct menu_list *list, struct lcd_menu *menu)
+{
+	menu_func_t entry;
+
+	if (!list)
+		return;
+
+	if (!list->submenu_list)
+		return;
+
+	entry = list->submenu_list[list->currently_selected];
+
+	if (!entry)
+		return;
+
+	menu_entry_enter(menu, entry, false);
+}
+
 void menu_list_scroll_up(struct menu_list *list)
 {
 	if (!list)