Instead of relying on RTNL, codel_dump() can use READ_ONCE()
annotations.

There is no etf_change() yet, this patch imply aligns
this qdisc with others.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>