Fix some comments

[pwdcd]

No description provided.

[rustbot]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @Nadrieril (or someone else) some time within the next two weeks.

Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (S-waiting-on-review and S-waiting-on-author) stays updated, invoking these commands when appropriate:

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[rustbot]

The rustc-dev-guide subtree was changed. If this PR only touches the dev guide consider submitting a PR directly to rust-lang/rustc-dev-guide otherwise thank you for updating the dev guide with your changes.

cc @BoxyUwU, @jieyouxu, @Kobzol

This PR changes MIR

cc @oli-obk, @RalfJung, @JakobDegen, @davidtwco, @vakaras

[oli-obk]

We've seen a wave of tiny fix PRs similar to yours that we suspect are linked with blockchain rewards. To avoid encouraging this we will not accept such PRs. If you would like to contribute to the project, you are more than welcome to contribute something more substantial