Merge branch 'ethtool-add-support-for-Fast-Link-Down-as-new-PHY-tunable'

Heiner Kallweit says:

====================
ethtool: add support for Fast Link Down as new PHY tunable

This adds support for Fast Link Down as new PHY tunable.
Fast Link Down reduces the time until a link down event is reported
for 1000BaseT. According to the standard it's 750ms what is too long
for several use cases.

This is the kernel-related series, the ethtool userspace extension
I'd submit once the kernel part has been applied.

v2:
- add describing comment in patch 1
====================

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