IPoIB: Fix error path in ipoib_mcast_dev_flush()

Don't leak memory on allocation failure for broadcast mcast group.
Also, print a warning to match handling for other mcast groups.

Signed-off-by: Eli Cohen <[e-mail]>
Signed-off-by: Michael S. Tsirkin <[e-mail]>
Signed-off-by: Roland Dreier <[e-mail]>

drivers/infiniband/ulp/ipoib/ipoib_multicast.c

···
 					&priv->multicast_tree);
 
 			list_add_tail(&priv->broadcast->list, &remove_list);
-		}
-
-		priv->broadcast = nmcast;
+			priv->broadcast = nmcast;
+		} else
+			ipoib_warn(priv, "could not reallocate broadcast group "
+                        	          IPOIB_GID_FMT "\n",
+                                	  IPOIB_GID_ARG(priv->broadcast->mcmember.mgid));
 	}
 
 	spin_unlock_irqrestore(&priv->lock, flags);