[clang] [mlir] [CIR] Honor the Direct coercion offset in x86_64 callconv lowering (PR #220724)

[Andy Kaylor via cfe-commits]

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

lgtm, with a minor quibble remaining about the getDirect() argument ordering. I suppose I can live with that either way.

https://github.com/llvm/llvm-project/pull/220724