Move more of `rustc::lint` into `rustc_lint`
Based on https://github.com/rust-lang/rust/pull/67806.
Here we try to consolidate more of the linting infra into `rustc::lint`. Some high-level notes:
- We now store an `Lrc<dyn Any + Send + Sync>` as opposed to `Lrc<LintStore>` in the `GlobalCtxt`. This enables us to avoid referring to the type, breaking a cyclic dependency, and so we can move things from `rustc::lint` to `rustc_lint`.
- `in_derive_expansion` is, and needs to, be moved as a method on `Span`.
- We reduce the number of ways on `tcx` to emit a lint so that the developer UX is more streamlined.
- `LintLevelsBuilder` is moved to `rustc_lint::levels`, leaving behind `LintLevelMap/Set` in a purified form due to current constraints (hopefully fixable in the future after https://github.com/rust-lang/rust/pull/68133).
- `struct_lint_level` is moved to `rustc::lint` due to current dependency constraints.
- `rustc::lint::context` is moved to `rustc_lint::context`.
- The visitors in `rustc::lint` are moved to `rustc_lint::passes`.