net: aquantia: Fix hardware reset when SPI may rarely hangup

Under some circumstances (notably using thunderbolt interface) SPI
on chip reset may be in active transaction.
Here we forcibly cleanup SPI to prevent possible hangups.

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