8263891: Changes for 8076985 missed the fix.

Reviewed-by: roland

Author: Vladimir Kozlov

src/hotspot/cpu/x86/x86_64.ad

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2003, 2020, Oracle and/or its affiliates. All rights reserved.
+// Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
 // DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 //
 // This code is free software; you can redistribute it and/or modify it
@@ -1648,7 +1648,7 @@ bool Matcher::const_oop_prefer_decode() {
 
 bool Matcher::const_klass_prefer_decode() {
   // Prefer ConP over ConNKlass+DecodeNKlass.
-  return true;
+  return false;
 }
 
 // Is it better to copy float constants, or load them directly from