Merge branch 'nfp-ethtool-flash-updates'

Jakub Kicinski says:

====================
nfp: ethtool flash updates

Dirk says:

This series adds the ability to update the control FW with ethtool.

It should be noted that the locking scheme here is to release the RTNL
lock before the flashing operation and to take it again afterwards to
ensure consistent state from the core code point of view. In this time,
we take a reference to the device to prevent the device being freed
while its being flashed.

This provides protection for the device being flashed while at the same
time not holding up any networking related functions which would
otherwise be locked out due to RTNL being held.
====================

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