net: defer netdev_name_node_alt_flush() call to netdev_run_todo()

net: defer netdev_name_node_alt_flush() call to netdev_run_todo()

In the following patch, we want to call rtnl_fill_prop_list() without
RTNL being held, but after a device reference was taken.

We need to free altnames in netdev_run_todo() instead of
unregister_netdevice_many_notify().

Freeing will only happen once all device references
have been released.

Note that dev->name_node serves as the anchor for altnames,
thus must be also freed in netdev_run_todo().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260525083542.1565964-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>