Add Support for Post Processing Effects (#3616)

* Add Post Processing Effects

* fix events and shader issues

* fix gtk upscale slider value

* fix bgra games

* don't swap swizzle if already swapped

* restore opengl texture state after effects run

* addressed review

* use single pipeline for smaa and fsr

* call finish on all pipelines

* addressed review

* attempt fix file case

* attempt fixing file case

* fix filter level tick frequency

* adjust filter slider margins

* replace fxaa shaders with original shader

* addressed review

Ryujinx.Graphics.OpenGL/Effects/IScalingFilter.cs

@@ -0,0 +1,18 @@
+using Ryujinx.Graphics.GAL;
+using Ryujinx.Graphics.OpenGL.Image;
+using System;
+
+namespace Ryujinx.Graphics.OpenGL.Effects
+{
+    internal interface IScalingFilter : IDisposable
+    {
+        float Level { get; set; }
+        void Run(
+            TextureView view,
+            TextureView destinationTexture,
+            int width,
+            int height,
+            Extents2D source,
+            Extents2D destination);
+    }
+}