Auto merge of #113902 - Enselic:lint-recursive-drop, r=oli-obk

Make `unconditional_recursion` warning detect recursive drops

Closes #55388

Also closes #50049 unless we want to keep it for the second example which this PR does not solve, but I think it is better to track that work in #57965.

r? `@oli-obk` since you are the mentor for #55388

Unresolved questions:
- [x] There are two false positives that must be fixed before merging (see diff). I suspect the best way to solve them is to perform analysis after drop elaboration instead of before, as now, but I have not explored that any further yet. Could that be an option? **Answer:** Yes, that solved the problem.

`@rustbot` label +T-compiler +C-enhancement +A-lint

Author: bors