[llvm] Enable logf128 constant folding for AArch64 (PR #96287)

[Eli Friedman via llvm-commits]

efriedma-quic wrote:

Oh, I see, gcc 13 has _Float128, and on older versions glibc typedefs it to long double.

Can we make this not AArch64-specific?  It seems like it affects any target where long double is 128 its.

https://github.com/llvm/llvm-project/pull/96287