net: add rb_to_skb() and other rb tree helpers

Geeralize private netem_rb_to_skb()

TCP rtx queue will soon be converted to rb-tree,
so we will need skb_rbtree_walk() helpers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 18a4c0eab2623cc95be98a1e6af1ad18e7695977)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2 files changed