Broken links in compiler internal docs

[bjorn3]

Take for example https://doc.rust-lang.org/nightly/nightly-rustc/rustc_codegen_ssa/traits/consts/trait.ConstMethods.html:

If you click on a reference to LocalInternedString you will be send to https://doc.rust-lang.org/nightly/syntax_pos/symbol/struct.LocalInternedString.html. Note the missing /nightly-rustc/.

This happens at other places too.