[llvm] [bolt] Support arm64 FP register spills (PR #73021)

[via llvm-commits]

eleviant wrote:

> Hi. I would check it later. That time: is it necessary to create yaml test instead of asm?

I have to emit ELF executable (with reloc), not just object so I need either both asm and linker or yaml that's why I've chosen the latter. 

> Do we need to check output after bolt?

No. This is minimal code snippet to trigger crash in bolt, not a real jump table. The output of bolt is no different from input here.

https://github.com/llvm/llvm-project/pull/73021