Protect against NULL cpuset when not bound

This commit was SVN r31600.

orte/mca/ess/base/ess_base_fns.c

@@ -294,6 +294,7 @@ int orte_ess_base_proc_binding(void)
     /* store our cpuset for exchange with non-peers
      * so that other procs in a comm_spawn can know it
      */
+    if (NULL != orte_process_info.cpuset) {
         OBJ_CONSTRUCT(&kv, opal_value_t);
         kv.key = strdup(OPAL_DSTORE_CPUSET);
         kv.type = OPAL_STRING;
@@ -306,6 +307,7 @@ int orte_ess_base_proc_binding(void)
             goto error;
         }
         OBJ_DESTRUCT(&kv);
+    }
     return ORTE_SUCCESS;
 
  error: