Apply suggestions from code review

commit suggestion of not always pretty printing

Co-authored-by: Urgau <3616612+Urgau@users.noreply.github.com>

Author: sassman

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -120,7 +120,7 @@ fn codegen_fn_attrs(tcx: TyCtxt<'_>, did: LocalDefId) -> CodegenFnAttrs {
                     mixed_export_name_no_mangle_lint_state.track_no_mangle(
                         attr.span,
                         tcx.local_def_id_to_hir_id(did),
-                        rustc_ast_pretty::pprust::attribute_to_string(attr),
+                        attr,
                     );
                 } else {
                     tcx.dcx()
@@ -792,7 +792,7 @@ struct MixedExportNameAndNoMangleState {
     export_name: Option<Span>,
     hir_id: Option<HirId>,
     no_mangle: Option<Span>,
-    no_mangle_attr_name: Option<String>,
+    no_mangle_attr: Option<&'a ast::Attribute>,
 }
 
 impl MixedExportNameAndNoMangleState {
@@ -821,7 +821,7 @@ impl MixedExportNameAndNoMangleState {
                 no_mangle,
                 errors::MixedExportNameAndNoMangle {
                     no_mangle,
-                    no_mangle_attr: no_mangle_attr_name,
+                    no_mangle_attr: rustc_ast_pretty::pprust::attribute_to_string(no_mangle_attr),
                     export_name,
                     removal_span: no_mangle,
                 },