OS-1571 Placate gcc -Wparentheses
Reviewed by: Robert Mustacchi <rm@joyent.com>

@@ -1168,11 +1168,11 @@
                 zerror(zlogp, B_TRUE, "failed to add standard symlink");
                 goto cleanup;
         }
 
         /* Add user-specified devices and directories */
-        if (err = zonecfg_setdevent(snap_hndl)) {
+        if ((err = zonecfg_setdevent(snap_hndl)) != 0) {
                 zerror(zlogp, B_FALSE, "%s: %s", zone_name,
                     zonecfg_strerror(err));
                 goto cleanup;
         }
         while (zonecfg_getdevent(snap_hndl, &ztab) == Z_OK) {