Merge branch 'simplify-TCP-loss-marking-code'

Yuchung Cheng says:

====================
simplify TCP loss marking code

The TCP loss marking is implemented by a set of intertwined
subroutines. TCP has several loss detection algorithms
(RACK, RFC6675/FACK, NewReno, etc) each calls a subset of
these routines to mark a packet lost. This has led to
various bugs (and fixes and fixes of fixes).

This patch set is to consolidate the loss marking code so
all detection algorithms call the same routine tcp_mark_skb_lost().
====================

Signed-off-by: David S. Miller <davem@davemloft.net>