r8169: implement additional ethtool stats ops

This adds support for ethtool standard statistics, and makes use of the
extended hardware statistics being available from RTl8125.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/58e0da73-a7dd-4be3-82ae-d5b3f9069bde@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>