[clang] [Driver] Add options to control workaround for Cortex-A53 Erratum 843419 (PR #143915)

[David Green via cfe-commits]

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

I think this LGTM. I left a comment for maybe having a "IsPossiblyACortexA53" check that would could reuse in a few places, but that is probably best extended as a separate issue.

https://github.com/llvm/llvm-project/pull/143915