Shader Extra Set Support + Cleanup (#36)

Separate samplers are now supported and arrays in constant sets are bound

src/Ryujinx.Graphics.Metal/Shaders/BlitMs.metal

@@ -13,7 +13,7 @@ struct Textures
 };
 
 fragment float4 fragmentMain(CopyVertexOut in [[stage_in]],
-                             constant Textures &textures [[buffer(22)]],
+                             constant Textures &textures [[buffer(TEXTURES_INDEX)]],
                              uint sample_id [[sample_id]]) {
     uint2 tex_size = uint2(textures.texture.get_width(), textures.texture.get_height());
     uint2 tex_coord = uint2(in.uv * float2(tex_size));