[compiler-rt] [XRay][RISC-V] Guard trampoline FP saves behind float ABI (PR #214390)

[Sam Elliott via llvm-commits]

lenary wrote:

I am not super familiar with xray, but in basically every single review like this I end up asking: should we be keying this off the ABI or the architecture? What happens if your library is built for `-mabi=lp64 -march=rv64imafd` (or any other combination where you have more FP state than the ABI treats as saved)

Depending on how xray is linked/used, there are different answers, but at least the question needs to be thought about.

https://github.com/llvm/llvm-project/pull/214390