qt-gui: Added GPU device selection functionality (#399)

* qt-gui: Added GPU device selection functionality

* Getting list of GPU only when application starts

* Fixed formatting

* Fixed formatting

* Fixed formatting

* Added warning when GPU doesn't support API version.

* Changed Unsupported Vulkan Version warning

* Removed unused size checking on GetPhysicalDevices

The method is only being called once so this doesn't make sense. It was some left over of me trying to get this done some other way.

* Fix formatting

* Fix formatting

* SettingsDialog: Passing physical devices as span

* Fixed formatting

src/qt_gui/settings_dialog.h

@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include <span>
 #include <QDialog>
 #include <QPushButton>
 
@@ -16,7 +17,7 @@ class SettingsDialog;
 class SettingsDialog : public QDialog {
     Q_OBJECT
 public:
-    explicit SettingsDialog(QWidget* parent = nullptr);
+    explicit SettingsDialog(std::span<const QString> physical_devices, QWidget* parent = nullptr);
     ~SettingsDialog();
 
     int exec() override;