Merge branch 'ethtool-add-pause-frame-stats'

Jakub Kicinski says:

====================
ethtool: add pause frame stats

This is the first (small) series which exposes some stats via
the corresponding ethtool interface. Here (thanks to the
excitability of netlink) we expose pause frame stats via
the same interfaces as ethtool -a / -A.

In particular the following stats from the standard:
 - 30.3.4.2 aPAUSEMACCtrlFramesTransmitted
 - 30.3.4.3 aPAUSEMACCtrlFramesReceived

4 real drivers are converted, I believe we got confirmation
from maintainers that all exposed stats match the standard.

v3:
 - fix mlx5 build
 - adjust the init logic in patch 1
v2:
 - netdevsim: add missing static
 - bnxt: fix sparse warning
 - mlx5: address Saeed's comments
====================

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