Revert "[Driver] Mark m_x86_Features_Group options as TargetSpecific"

This broke cross-builds of llvm from x86_64 to arm64 mac, see
comment on
https://github.com/llvm/llvm-project/commit/1d6c3e29f6aa45914faa7be00a939b8f550f38e9

> so that they get an error on non-x86 targets.
> Follow-up to D151590.
>
> As a workaround for https://github.com/llvm/llvm-project/issues/63270, we don't
> report an error for -msse4.2.

This reverts commit 1d6c3e29.