[llvm] [TLI] Pass replace-with-veclib works with Scalable Vectors. (PR #73642)

[Maciej Gabka via llvm-commits]

mgabka wrote:

> The below functions were not vectorized:
> 
> In test `intrinsics-with-veclib-sleef-scalable.ll`:
> 
> * `ceil`, `copysign`, `fabs`, `fabs`, `floor`, `fma`, `maxnum`, `minnum`, `nearbyint`, `pow`, `rint`, `round`, `sqrt`, `trunc`
> * All 14 of them do not have a vectorized variant (i.e., `isFunctionVectorizable` is false)

That feels like LLVM is missing some SLEEF mappings which should be added later.

https://github.com/llvm/llvm-project/pull/73642