Merge branch 'aquantia-various-ethtool-ops-implementation'

Igor Russkikh says:

====================
net: aquantia: various ethtool ops implementation

In this patchset Anton Mikaev and I added some useful ethtool operations:
- ring size changes
- link renegotioation
- flow control management

The patch also improves init/deinit sequence.

V3 changes:
- After review and analysis it is clear that rtnl lock (which is
  captured by default on ethtool ops) is enough to secure possible
  overlapping of dev open/close. Thus, just dropping internal mutex.

V2 changes:
- using mutex to secure simultaneous dev close/open
- using state var to store/restore dev state
====================

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