[clang] [Sparc][clang] Match GCC's SPARC V8 vector argument passing (PR #222254)

[Folkert de Vries via cfe-commits]

folkertdev wrote:

Independent but related, the return ABI for these vectors is also inconsistent

https://llvm.godbolt.org/z/zfYPojTjE

https://github.com/llvm/llvm-project/pull/222254