[llvm] [X86][SSE] Don't emit SSE2 load instructions in SSE1-only mode (PR #134547)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon requested changes to this pull request.

Thanks for the fix - it should be a candidate for cherry picking back to 20.x once its been in trunk for a few days - we don't provide patches for 19.x any more though.

https://github.com/llvm/llvm-project/pull/134547