Avalonia - Couple fixes and improvements to vulkan (#3483)

* drop split devices, rebase

* add fallback to opengl if vulkan is not available

* addressed review

* ensure present image references are incremented and decremented when necessary

* allow changing vsync for vulkan

* fix screenshot on avalonia vulkan

* save favorite when toggled

* improve sync between popups

* use separate devices for each new window

* fix crash when closing window

* addressed review

* don't create the main window with immediate mode

* change skia vk delegate to method

* update vulkan throwonerror

* addressed review

Ryujinx.Ava/Ui/Backend/Vulkan/ResultExtensions.cs

@@ -7,7 +7,8 @@ namespace Ryujinx.Ava.Ui.Vulkan
     {
         public static void ThrowOnError(this Result result)
         {
-            if (result != Result.Success)
+            // Only negative result codes are errors.
+            if ((int)result < (int)Result.Success)
             {
                 throw new Exception($"Unexpected API error \"{result}\".");
             }