Fix and rename overflow_check_conditional

[Jarcho]

fixes #2457

Other changes:

• Limit the lint to unsigned types.
• Actually check if the operands are the same rather than using only the first part of the path.
• Allow the repeated expression to be anything as long as there are no side effects.

changelog: Rename overflow_check_conditional to panicking_overflow_check and move to correctness

[rustbot]

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[bors]

☔ The latest upstream changes (presumably #12974) made this pull request unmergeable. Please resolve the merge conflicts.

[y21]

Looks good, r=me with merge conflicts fixed

[y21]

@bors r+

[bors]

📌 Commit d2ff2b9 has been approved by y21

It is now in the queue for this repository.

[bors]

⌛ Testing commit d2ff2b9 with merge b012421...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: y21
Pushing b012421 to master...