Prereq3 for async drop - LangItem registration for async_drop_in_place()::{{closure0}}

[azhogin]

This is subpart 3 PR of #123948, just for review purposes.
We have async_drop_in_place lang item for async fn async_drop_in_place<T>(...).

#[lang = "async_drop_in_place"]
pub async unsafe fn async_drop_in_place<T: ?Sized>(_to_drop: *mut T) { ... }

But we also need to generate shim for its returning value - coroutine async_drop_in_place<T>::{{closure0}}.
So, we need to bind some lang item to it. This patch registers LangItem::AsyncDropInPlacePoll for coroutine, when its constructor function is LangItem::AsyncDropInPlace.

Review only last commit, based on previous PR #129736

[rustbot]

Some changes occurred to the CTFE / Miri engine

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This PR changes Stable MIR

cc @oli-obk, @celinval, @ouz-a

This PR changes MIR

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Some changes occurred in compiler/rustc_codegen_cranelift

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Some changes occurred to MIR optimizations

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[bors]

☔ The latest upstream changes (presumably #130724) made this pull request unmergeable. Please resolve the merge conflicts.

[davidtwco]

r? @nikomatsakis is going to look into this

[bors]

☔ The latest upstream changes (presumably #136751) made this pull request unmergeable. Please resolve the merge conflicts.

[bors]

☔ The latest upstream changes (presumably #136943) made this pull request unmergeable. Please resolve the merge conflicts.