IB/core: Do not notify GID change event of an unregistered device

When IB device is undergoing unregistration, the GID cache is always
cleaned up after all clients are unregistered with the below flow.

__ib_unregister_device()
  disable_device()
  ib_cache_cleanup_one()
    gid_table_cleanup_one()
      cleanup_gid_table_port()

There is no use in generating a GID change event at this stage, where
there is no active client of the device and device is nearly unregistered.

Link: https://lore.kernel.org/r/20191020065427.8772-4-leon@kernel.orgSigned-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/cache.c

@@ -819,22 +819,16 @@ static void cleanup_gid_table_port(struct ib_device *ib_dev, u8 port,
 				   struct ib_gid_table *table)
 {
 	int i;
-	bool deleted = false;
 
 	if (!table)
 		return;
 
 	mutex_lock(&table->lock);
 	for (i = 0; i < table->sz; ++i) {
-		if (is_gid_entry_valid(table->data_vec[i])) {
+		if (is_gid_entry_valid(table->data_vec[i]))
 			del_gid(ib_dev, port, table, i);
-			deleted = true;
-		}
 	}
 	mutex_unlock(&table->lock);
-
-	if (deleted)
-		dispatch_gid_change_event(ib_dev, port);
 }
 
 void ib_cache_gid_set_default_gid(struct ib_device *ib_dev, u8 port,