add configurable Vulkan present modes

Co-authored-by: Techx3 <56268269+Techx3@users.noreply.github.com>

src/common/emulatorConfig.cpp

@@ -38,6 +38,10 @@ const std::string& GetUserName() {
 	return g_config->user_name;
 }
 
+PresentMode GetPresentMode() {
+	return g_config->present_mode;
+}
+
 bool FullscreenEnabled() {
 	return g_config->fullscreen_enabled;
 }