net: aquantia: Improve adapter init/deinit logic

We now pass link drop status to FW on init/deinit. This is required
to inform FW that driver took/released a control on link.
FW then will manage its own state and device power profile based
on this information. To improve management we remove mpi_set
function which ambiguously took both state and speed parameters.

Deinit callback is now a part of FW ops, as it actually manages the FW.

Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>