Rollup merge of rust-lang#80527 - jyn514:rustdoc-lints, r=GuillaumeGomez

Make rustdoc lints a tool lint instead of built-in

- Rename `broken_intra_doc_links` to `rustdoc::broken_intra_doc_links` (and similar for other rustdoc lints; I don't expect any others to be used frequently, though).
- Ensure that the old lint names still work and give deprecation errors
- Register lints even when running doctests
- Move lint machinery into a separate file
- Add `declare_rustdoc_lint!` macro

Unblocks rust-lang#80300, rust-lang#79816, rust-lang#80965. Makes the strangeness in rust-lang#77364 more apparent to the end user (note that `missing_docs` is *not* moved to rustdoc in this PR). Closes rust-lang#78786.

## Current status

This is blocked on rust-lang#82620 (see rust-lang#80527 (comment))

Author: JohnTitor

core/src/lib.rs

@@ -297,7 +297,8 @@ pub mod primitive;
     unused_imports,
     unsafe_op_in_unsafe_fn
 )]
-#[allow(non_autolinks)]
+#[cfg_attr(bootstrap, allow(non_autolinks))]
+#[cfg_attr(not(bootstrap), allow(rustdoc::non_autolinks))]
 // FIXME: This annotation should be moved into rust-lang/stdarch after clashing_extern_declarations is
 // merged. It currently cannot because bootstrap fails as the lint hasn't been defined yet.
 #[allow(clashing_extern_declarations)]