net: usb: aqc111: Various callbacks implementation

Reset, stop callbacks, driver unbind callback.
More register defines required for these callbacks.
Add helpers to read/write 16bit values

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