[ HLSL] Implement `tanh` intrinsic

[farzonl]

Implement HLSL tanh intrinsic:

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

part of this proposal: https://discourse.llvm.org/t/rfc-all-the-math-intrinsics/78294

Four parts:

1. DXIL backend change
2. SPIRV backend change
3. HLSL frontend change
4. Constraint intrinsic change