[rustdoc] Jump to definition feature tries to infer `cfg`ed-out items

[GuillaumeGomez]

[compiler-errors]

Is this issue gonna get filled out? Seems a bit empty.

[GuillaumeGomez]

For that I need to check why cfg-ed out items are actually processed by rustdoc. My current guess is that the items are still part of the HIR and when we use the HIR visitor, it gives rustdoc the items whereas it shouldn't.

Anyway, on my TODO list.