Make multiple_unsafe_ops_per_block ignore await desugaring

[Noratrieb]

The await desugaring contains two calls (Poll::new_unchecked and get_context) inside a single unsafe block. That violates the lint.

fixes #11312

changelog: [multiple_unsafe_ops_per_block]: fix false positives in .await

[rustbot]

r? @giraffate

(rustbot has picked a reviewer for you, use r? to override)

[Centri3]

We should really ignore any expansion, right? It's not like multiple operations always causes soundness problems or anything, and the author can't change it. Macros in the current crate I'm not sure, but I'd err on the safe side.

[bend-n]

ignore any expansion

It would be interesting if that was done for all warnings, but I don't see why it should be special cased for this one?
You get meaningless warnings from macros fairly often, and while it would be nice to not have them, it doesnt really make sense for it to only apply to multiple_unsafe_ops_per_block.

[Centri3]

This is already done for most lints, so no, it shouldn't be special cased for this one :)

There are reasons to lint macro-generated code though, for example when it's UB or almost certainly incorrect

[giraffate]

@bors r+

Thanks!

[bors]

📌 Commit 6ed04af has been approved by giraffate

It is now in the queue for this repository.

[bors]

⌛ Testing commit 6ed04af with merge 2cf708d...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: giraffate
Pushing 2cf708d to master...

[ferologics]

thanks for fixing this here @Nilstrieb 🙇