`miri` no longer builds after rust-lang/rust#63561

[rust-highfive]

Hello, this is your friendly neighborhood mergebot.
After merging PR #63561, I observed that the tool miri no longer builds.
A follow-up PR to the repository https://github.com/rust-lang/miri is needed to fix the fallout.

cc @HeroicKatora, do you think you would have time to do the follow-up work?
If so, that would be great!

cc @oli-obk, the PR reviewer, and @rust-lang/compiler -- nominating for prioritization.

[oli-obk]

I need to port parts of tag_allocation from miri to rustc and only keep the actual miri-parts in miri. I'll try to get it done by tomorrow night.

[nikomatsakis]

check-in from compiler triage:

Go @oli-obk, go! 🐎