7045397: NPG: Add freelists to class loader arenas

Reviewed-by: coleenp, stefank, jprovino, ohair

hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/freeChunk.hpp

@@ -133,7 +133,7 @@ class FreeChunk VALUE_OBJ_CLASS_SPEC {
   }
 
   // Return the address past the end of this chunk
-  HeapWord* end() const { return ((HeapWord*) this) + size(); }
+  uintptr_t* end() const { return ((uintptr_t*) this) + size(); }
 
   // debugging
   void verify()             const PRODUCT_RETURN;