hir: Remove opt_local_def_id_to_hir_id and opt_hir_node_by_def_id

Also replace a few `hir_node()` calls with `hir_node_by_def_id()`

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -1969,13 +1969,10 @@ impl<'tcx> WfCheckingCtxt<'_, 'tcx> {
             // Match the existing behavior.
             if pred.is_global() && !pred.has_type_flags(TypeFlags::HAS_BINDER_VARS) {
                 let pred = self.normalize(span, None, pred);
-                let hir_node = tcx.opt_hir_node_by_def_id(self.body_def_id);
 
                 // only use the span of the predicate clause (#90869)
-
-                if let Some(hir::Generics { predicates, .. }) =
-                    hir_node.and_then(|node| node.generics())
-                {
+                let hir_node = tcx.hir_node_by_def_id(self.body_def_id);
+                if let Some(hir::Generics { predicates, .. }) = hir_node.generics() {
                     span = predicates
                         .iter()
                         // There seems to be no better way to find out which predicate we are in