Auto merge of rust-lang#77253 - jyn514:crate-link, r=Manishearth

Resolve `crate` in intra-doc links properly across crates

Closes rust-lang#77193; see rust-lang#77193 (comment) for an explanation of what's going on here.
~~This also fixes the BTreeMap docs that have been broken for a while; see the description on the second commit for why and how.~~ Nope, see the second commit for why the link had to be changed.

r? `@Manishearth`
cc `@dylni`

`@dylni` note that this doesn't solve your original problem - now _both_ `with_code` and `crate::with_code` will be broken links. However this will fix a lot of other broken links (in particular I think https://docs.rs/sqlx/0.4.0-beta.1/sqlx/query/struct.Query.html is because of this bug). I'll open another issue for resolving additional docs in the new scope.

Author: bors

alloc/src/collections/btree/map.rs

@@ -811,7 +811,7 @@ impl<K: Ord, V> BTreeMap<K, V> {
     /// types that can be `==` without being identical. See the [module-level
     /// documentation] for more.
     ///
-    /// [module-level documentation]: crate::collections#insert-and-complex-keys
+    /// [module-level documentation]: index.html#insert-and-complex-keys
     ///
     /// # Examples
     ///