10109 libzonecfg needs a smatch fix

@@ -20,10 +20,11 @@
  */
 
 /*
  * Copyright 2014 Gary Mills
  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, Joyent, Inc.
  * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
  */
 
 #include <libsysevent.h>
 #include <pthread.h>

@@ -2979,12 +2980,12 @@
         }
 
         if (strlen(path) <= g_devwalk_skip_prefix)
                 return (0);
 
-        g_devwalk_cb(path + g_devwalk_skip_prefix, st->st_uid, st->st_gid,
-            st->st_mode & S_IAMB, acl_txt != NULL ? acl_txt : "",
+        (void) g_devwalk_cb(path + g_devwalk_skip_prefix, st->st_uid,
+            st->st_gid, st->st_mode & S_IAMB, acl_txt != NULL ? acl_txt : "",
             g_devwalk_data);
         free(acl_txt);
         return (0);
 }