Merge branch 'dsa-port-mirroring'

Florian Fainelli says:

====================
net: dsa: Port mirroring support

This patch series adds support for port mirroring in the two
Broadcom switch drivers. The major part of the functional are actually with
the plumbing between tc and the drivers.

Changes in v5:

- Added Jiri's Reviewed-by tag to first patch
- rebase against latest net-next/master after bcm_sf2 CFP series

Changes in v4:

- rebased against latest net-next/master after Vivien's changes

Changes in v3:

- removed multiline comments from added structures
- simplify error handling in dsa_slave_add_cls_matchall

Changes in v2:

- fixed filter removal logic to disable the ingress or egress mirroring
  when there are no longer ports being monitored in ingress or egress

- removed a stray list_head in dsa_port structure that is not used

Tested using the two iproute2 examples:

      tc qdisc  add dev eth1 handle ffff: ingress
      tc filter add dev eth1 parent ffff:           \
               matchall skip_sw                      \
               action mirred egress mirror           \
               dev eth2
      tc qdisc add dev eth1 handle 1: root prio
      tc filter add dev eth1 parent 1:               \
               matchall skip_sw                       \
               action mirred egress mirror            \
               dev eth2
====================

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