[clang] [llvm] [WebAssembly] Add `-i128:128` to the `datalayout` string. (PR #119204)

[Derek Schuff via llvm-commits]

https://github.com/dschuff approved this pull request.

LGTM for updating the LLVM datalayout string to match clang's, I don't think this should affect clang's ABI at all.

https://github.com/llvm/llvm-project/pull/119204