[llvm] [Support] Use all_read | all_write for createTemporaryFile (PR #83360)

[Martin Storsjö via llvm-commits]

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

This looks reasonable. I guess it's possible, but unlikely, that it does affect some case somewhere, but we'll never know unless we roll it out. So LGTM.

https://github.com/llvm/llvm-project/pull/83360