[libunwind] [libunwind][Haiku] Fix signal frame unwinding (PR #135367)

[Trung Nguyen via cfe-commits]

trungnt2910 wrote:

You mean adding support for `i386`?

>From what I understand about the linked issue, x86 is failing due to some signal frame unwinding function prototypes got leaked to general Haiku code, `_LIBUNWIND_TARGET_HAIKU`, but the implementation part got an additional `_LIBUNWIND_TARGET_X86_64` check.

This PR guards both under `_LIBUNWIND_CHECK_HAIKU_SIGRETURN`, which has both the OS and architecture checks, effectively "fixing" `i386`.




https://github.com/llvm/llvm-project/pull/135367