rustdoc: Fix invalid suggestions on ambiguous intra doc links v2
Fixes https://github.com/rust-lang/rust/issues/108653.
This is another approach to fixing the same issue. This time, we keep the computed information around instead of re-computing it.
Strangely enough, the order for ambiguities seem to have been changed. Not an issue but it creates a lot of diff...
So which version do you prefer?
r? `@notriddle`