Implement Zero-Configuration Resolution Scaling (#1365)

* Initial implementation of Render Target Scaling

Works with most games I have. No GUI option right now, it is hardcoded.

Missing handling for texelFetch operation.

* Realtime Configuration, refactoring.

* texelFetch scaling on fragment shader (WIP)

* Improve Shader-Side changes.

* Fix potential crash when no color/depth bound

* Workaround random uses of textures in compute.

This was blacklisting textures in a few games despite causing no bugs. Will eventually add full support so this doesn't break anything.

* Fix scales oscillating when changing between non-native scales.

* Scaled textures on compute, cleanup, lazier uniform update.

* Cleanup.

* Fix stupidity

* Address Thog Feedback.

* Cover most of GDK's feedback (two comments remain)

* Fix bad rename

* Move IsDepthStencil to FormatExtensions, add docs.

* Fix default config, square texture detection.

* Three final fixes:

- Nearest copy when texture is integer format.
- Texture2D -> Texture3D copy correctly blacklists the texture before trying an unscaled copy (caused driver error)
- Discount small textures.

* Remove scale threshold.

Not needed right now - we'll see if we run into problems.

* All CPU modification blacklists scale.

* Fix comment.

Ryujinx.Graphics.Shader/TextureDescriptor.cs

@@ -13,6 +13,8 @@ namespace Ryujinx.Graphics.Shader
         public int CbufSlot   { get; }
         public int CbufOffset { get; }
 
+        public TextureUsageFlags Flags { get; set; }
+
         public TextureDescriptor(string name, SamplerType type, int handleIndex)
         {
             Name        = name;
@@ -23,6 +25,8 @@ namespace Ryujinx.Graphics.Shader
 
             CbufSlot   = 0;
             CbufOffset = 0;
+
+            Flags = TextureUsageFlags.None;
         }
 
         public TextureDescriptor(string name, SamplerType type, int cbufSlot, int cbufOffset)
@@ -35,6 +39,8 @@ namespace Ryujinx.Graphics.Shader
 
             CbufSlot   = cbufSlot;
             CbufOffset = cbufOffset;
+
+            Flags = TextureUsageFlags.None;
         }
     }
 }