Initial support for shader attribute indexing (#2546)

* Initial support for shader attribute indexing

* Support output indexing too, other improvements

* Fix order

* Address feedback

Ryujinx.Graphics.Gpu/Shader/ShaderCache.cs

@@ -40,7 +40,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
         /// <summary>
         /// Version of the codegen (to be changed when codegen or guest format change).
         /// </summary>
-        private const ulong ShaderCodeGenVersion = 2542;
+        private const ulong ShaderCodeGenVersion = 2546;
 
         // Progress reporting helpers
         private volatile int _shaderCount;