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

[Peter Smith via cfe-commits]

smithp35 wrote:

> > Personally I'd default to off, particularly after having clang default this to off for the last 10 years.
> 
> I didn't believe this changed the defaults (I may be mistaken, let me know if I am!). It was already enabled on Android + Fuchsia, and I believe this patch keeps that the same. It just adds an options to control it. Linux still does not enable it, only `isAndroid || isOHOSFamily` or Fuchsia through the other ToolChain.

My apologies, false alarm. I think I read too much into the description and less into the code. I've no objections. I'll update my comment with a please ignore.

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