Rollup merge of rust-lang#72365 - marmeladema:remove-node_to_hir_id, r=ecstatic-morse

Remove unused `StableHashingContext::node_to_hir_id` method

cc rust-lang#50928

Author: RalfJung

src/librustc_middle/ich/hcx.rs

@@ -135,11 +135,6 @@ impl<'a> StableHashingContext<'a> {
         self.definitions.def_path_hash(def_id)
     }
 
-    #[inline]
-    pub fn node_to_hir_id(&self, node_id: ast::NodeId) -> hir::HirId {
-        self.definitions.node_id_to_hir_id(node_id)
-    }
-
     #[inline]
     pub fn hash_bodies(&self) -> bool {
         self.hash_bodies