[llvm] [X86] Fix ABI for passing after i128 (PR #124134)

[Nikita Popov via llvm-commits]

nikic wrote:

Probably worth noting that it's expected that the frontend will directly pass via stack for things like `_BitInt(256)`. So things like `i256` and `<2 x i128>` on the IR level continue to use the YOLO ABI.

https://github.com/llvm/llvm-project/pull/124134