GetTileShape for packed formats

[walbourn]

I see there is specific handling of DXGI_FORMAT_R8G8_B8G8_UNORM and DXGI_FORMAT_G8R8_G8B8_UNORM in D3D12_PROPERTY_LAYOUT_FORMAT_TABLE::GetTileShape for volume textures.

What is confusing me is that the docs explicitly state:

Note the following formats are not supported with tiled resources: 96bpp formats, video formats, R1_UNORM, R8G8_B8G8_UNORM, R8R8_G8B8_UNORM.

https://learn.microsoft.com/en-us/windows/win32/direct3d12/volume-tiled-resources

[walbourn]

Looks like this limitation is stated in the specs:

https://microsoft.github.io/DirectX-Specs/d3d/archive/D3D11_3_FunctionalSpec.htm#5.9%20Tiled%20Resources

It seems like the extra code in D3DX12 is not needed for these formats.