Auto merge of #126068 - lqd:revert-124976, r=petrochenkov

Revert "use `tcx.used_crates(())` more" before it reaches beta

There are more open issues caused by #124976 than will be fixed by #125493 alone. The beta cut is soon, so let's revert it and buy some time to analyze and fix these issues in our own time.

fixes rust-lang/rust#125474
fixes rust-lang/rust#125484
fixes rust-lang/rust#125646
fixes rust-lang/rust#125707
fixes #126066
fixes #125934
fixes rust-lang/rust#126021

r? `@petrochenkov`
`@bors` p=1

clippy_utils/src/lib.rs

@@ -647,7 +647,7 @@ fn item_children_by_name(tcx: TyCtxt<'_>, def_id: DefId, name: Symbol) -> Vec<Re
 /// This function is expensive and should be used sparingly.
 pub fn def_path_res(cx: &LateContext<'_>, path: &[&str]) -> Vec<Res> {
     fn find_crates(tcx: TyCtxt<'_>, name: Symbol) -> impl Iterator<Item = DefId> + '_ {
-        tcx.crates_including_speculative(())
+        tcx.crates(())
             .iter()
             .copied()
             .filter(move |&num| tcx.crate_name(num) == name)