Merge branch 'ehtool-fec-stats'

Jakub Kicinski says:

====================
ethtool: add standard FEC statistics

This set adds uAPI for reporting standard FEC statistics, and
implements it in a handful of drivers.

The statistics are taken from the IEEE standard, with one
extra seemingly popular but not standard statistics added.

The implementation is similar to that of the pause frame
statistics, user requests the stats by setting a bit
(ETHTOOL_FLAG_STATS) in the common ethtool header of
ETHTOOL_MSG_FEC_GET.

Since standard defines the statistics per lane what's
reported is both total and per-lane counters:

 # ethtool -I --show-fec eth0
 FEC parameters for eth0:
 Configured FEC encodings: None
 Active FEC encoding: None
 Statistics:
  corrected_blocks: 256
    Lane 0: 255
    Lane 1: 1
  uncorrectable_blocks: 145
    Lane 0: 128
    Lane 1: 17

v2: check for errors in mlx5 register access
====================

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