[HLSL] implement `tan` intrinsic

[llvm-beanz]

Implement HLSL tan intrinsic:

https://learn.microsoft.com/en-us/windows/win32/direct3dhlsl/dx-graphics-hlsl-tan

[farzonl]

@llvm-beanz Can I have this one assigned to me?

[EugeneZelenko]

@farzonl: Just create pull request and mention it on this page.