Rollup merge of #118573 - petrochenkov:pathdatakind, r=TaKO8Ki

rustc: Harmonize `DefKind` and `DefPathData`

Follow up to rust-lang/rust#118188.

`DefPathData::(ClosureExpr,ImplTrait)` are renamed to match `DefKind::(Closure,OpaqueTy)`.

`DefPathData::ImplTraitAssocTy` is replaced with `DefPathData::TypeNS(kw::Empty)` because both correspond to `DefKind::AssocTy`.
It's possible that introducing `(DefKind,DefPathData)::AssocOpaqueTy` instead could be a better solution, but that would be a much more invasive change.

Const generic parameters introduced for effects are moved from `DefPathData::TypeNS` to `DefPathData::ValueNS`, because constants are values.

`DefPathData` is no longer passed to `create_def` functions to avoid redundancy.