IB/mthca: fix memory user DB table leak

Free the memory allocated in mthca_init_user_db_tab() when releasing
the db_tab in mthca_cleanup_user_db_tab().
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/mthca/mthca_memfree.c

@@ -485,6 +485,8 @@ void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
 			put_page(db_tab->page[i].mem.page);
 		}
 	}
+
+	kfree(db_tab);
 }
 
 int mthca_alloc_db(struct mthca_dev *dev, enum mthca_db_type type,