Slightly tweak comments wrt `lint_overflowing_range_endpoint` From the review: https://github.com/rust-lang/rust/pull/101986#discussion_r975610611 It _seemed_ that the lint was not emitted when the `if` check failed, but _actually_ this happens already in a special case and the lint is emitted outside of this function, if this function doesn't. I've cleared up the code/comments a bit, so it's more obvious :) r? ```@estebank```