Rollup merge of #153643 - TaKO8Ki:issue-153539, r=Kivooeo

Avoid projection-only suggestions for inherent assoc types

Fixes rust-lang/rust#153539.

Type mismatch diagnostics in `note_and_explain_type_err` currently route both `ty::Projectio`n and `ty::Inherent`
through the same associated-type suggestion path. For inherent associated types, that path can reach helpers that
are only valid for trait projections.

Author: JonathanBrouwer