mca_base_var: fix output bug about settable vars

Fix the test that determined whether we output "writeable" or
"read-only" for MCA vars (it was checking the wrong flag).

Signed-off-by: Jeff Squyres <jsquyres@cisco.com>
(cherry picked from commit 176da51aec0955a51f21157b33b21f60b6f28092)

opal/mca/base/mca_base_var.c

@@ -10,7 +10,7 @@
  *                         University of Stuttgart.  All rights reserved.
  * Copyright (c) 2004-2005 The Regents of the University of California.
  *                         All rights reserved.
- * Copyright (c) 2008-2015 Cisco Systems, Inc.  All rights reserved.
+ * Copyright (c) 2008-2018 Cisco Systems, Inc.  All rights reserved
  * Copyright (c) 2012-2018 Los Alamos National Security, LLC. All rights
  *                         reserved.
  * Copyright (c) 2014-2016 Intel, Inc. All rights reserved.
@@ -2146,7 +2146,8 @@ int mca_base_var_dump(int vari, char ***out, mca_base_var_dump_type_t output_typ
         asprintf(out[0] + line++, "%ssource:%s", tmp, source_string);
 
         /* Output whether it's read only or writable */
-        asprintf(out[0] + line++, "%sstatus:%s", tmp, VAR_IS_DEFAULT_ONLY(var[0]) ? "read-only" : "writeable");
+        asprintf(out[0] + line++, "%sstatus:%s", tmp,
+                VAR_IS_SETTABLE(var[0]) ? "writeable" : "read-only");
 
         /* Output the info level of this parametere */
         asprintf(out[0] + line++, "%slevel:%d", tmp, var->mbv_info_lvl + 1);