We got a little mixed up with what the backoff member holds in the
IPoIB multicast group structure: sometimes it was used as a number of
seconds, and sometimes it was used as a number of jiffies.  Fix the
code so that backoff is always in seconds.
Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
 
        mcast->dev = dev;
        mcast->created = jiffies;
-       mcast->backoff = HZ;
+       mcast->backoff = 1;
        mcast->logcount = 0;
 
        INIT_LIST_HEAD(&mcast->list);
                        IPOIB_GID_ARG(mcast->mcmember.mgid), status);
 
        if (!status && !ipoib_mcast_join_finish(mcast, mcmember)) {
-               mcast->backoff = HZ;
+               mcast->backoff = 1;
                down(&mcast_mutex);
                if (test_bit(IPOIB_MCAST_RUN, &priv->flags))
                        queue_work(ipoib_workqueue, &priv->mcast_task);
                if (test_bit(IPOIB_MCAST_RUN, &priv->flags))
                        queue_delayed_work(ipoib_workqueue,
                                           &priv->mcast_task,
-                                          mcast->backoff);
+                                          mcast->backoff * HZ);
                up(&mcast_mutex);
        } else
                mcast->query_id = ret;