Automatically add `-C target-feature=+tagged-globals` when `-Z sanitizer=hwaddress` is used

[Enselic]

We currently document that -C target-feature=+tagged-globals needs to be used with -Z sanitizer=hwaddress. But that is easy to miss. We forgot to do that in our own test for example (fixed by this PR).

We should probably do like clang and automatically enable that target-feature after thinking about how that affects Rust safety guarantees, for example. That was suggested here.

[nikunj-kohli]

I would like to contribute here, I request you to assign me

[Enselic]

Glad to hear that. But it's better if you do it yourself since you can. See https://rustc-dev-guide.rust-lang.org/rustbot.html#issue-claiming for how to do it.