[clang] [llvm] [HLSL] Implement the `degrees` intrinsic (PR #111209)

[Greg Roth via cfe-commits]

https://github.com/pow2clk commented:

None of my suggestions are essential, but I'll give you a chance to consider them even if you reject them all before I approve.

https://github.com/llvm/llvm-project/pull/111209