[llvm] [GlobalISel][AArch64] Legalize G_FABS and G_FNEG for SVE (PR #114784)

[Thorsten Schütt via llvm-commits]

tschuett wrote:

But then we could legalize G_ADD for wide fixed length vectors and add/generate patterns or do the work in C++.

https://github.com/llvm/llvm-project/pull/114784