7ca1c48bbb
rustc_typeck: adopt let else in more places Continuation of https://github.com/rust-lang/rust/pull/89933, https://github.com/rust-lang/rust/pull/91018, https://github.com/rust-lang/rust/pull/91481, https://github.com/rust-lang/rust/pull/93046, https://github.com/rust-lang/rust/pull/93590, https://github.com/rust-lang/rust/pull/94011. I have extended my clippy lint to also recognize tuple passing and match statements. The diff caused by fixing it is way above 1 thousand lines. Thus, I split it up into multiple pull requests to make reviewing easier. This PR handles rustc_typeck.
For high-level intro to how type checking works in rustc, see the type checking chapter of the rustc dev guide.