[llvm] Fix non-determinism in debuginfo (PR #68332)

[David Fang via llvm-commits]

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

I'm not familiar enough with the code base for my approval to be worth anything, but nevertheless I am thrilled this is getting fixed!

I only wish there was a better way to test for determinism in isolation.

https://github.com/llvm/llvm-project/pull/68332