Extend the ` x.py` policy for `TODO` and `FIXME` to other in-tree projects

[lcnr]

Proposal

It is not allowed to merge changes referencing TODO, meaning that while working on a change, one can use TODO for things which still have to be fixed before merging the PR. It's nice that this means one can simply grep for TODO in the code base or at least in ./compiler.

There are currently the following uses of TODO:

• rustc_codegen_cranelift: 5 uses
• rustc_codegen_gcc: 204 uses
• rustc_mir_build as the text of a suggestion: https://github.com/rust-lang/rust/blob/e96bb7e44fbcc23c1e6009e8d0ee8ab208668fb4/compiler/rustc_mir_build/src/check_unsafety.rs#L121-L123

I would like us to change the uses in rustc_codegen_cranelift and rustc_codegen_gcc to FIXME and ideally add a CI check to these projects as well. cc @bjorn3 @antoyo I think.

There are a lot more uses in /library and /src. While I would like to do that change there as well, I am not proposing this as part of this MCP.

Mentors or Reviewers

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Process

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You can read more about Major Change Proposals on forge.

[rustbot]

Important

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cc @rust-lang/compiler

[Kivooeo]

@rustbot second