inline is_mutable, make needs_to_be_mutable non-lazy

Author: ada4a

clippy_lints/src/methods/map_identity.rs

@@ -27,9 +27,8 @@ pub(super) fn check(
         let mut sugg = vec![(call_span, String::new())];
         let mut app = Applicability::MachineApplicable;
 
-        let needs_to_be_mutable = || cx.typeck_results().expr_ty_adjusted(expr).is_mutable_ptr();
-        let is_mutable = || is_mutable(cx, caller);
-        if needs_to_be_mutable() && !is_mutable() {
+        let needs_to_be_mutable = cx.typeck_results().expr_ty_adjusted(expr).is_mutable_ptr();
+        if needs_to_be_mutable && !is_mutable(cx, caller) {
             if let Some(hir_id) = path_to_local_with_projections(caller)
                 && let Node::Pat(pat) = cx.tcx.hir_node(hir_id)
                 && let PatKind::Binding(_, _, ident, _) = pat.kind