Rollup merge of #100909 - nnethercote:minor-ast-LitKind-improvement, r=petrochenkov

Minor `ast::LitKind` improvements

r? `@petrochenkov`

compiler/rustc_typeck/src/check/fn_ctxt/checks.rs

@@ -1136,7 +1136,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 opt_ty.unwrap_or_else(|| self.next_float_var())
             }
             ast::LitKind::Bool(_) => tcx.types.bool,
-            ast::LitKind::Err(_) => tcx.ty_error(),
+            ast::LitKind::Err => tcx.ty_error(),
         }
     }