net: fman: Move struct dev to mac_device

Move the reference to our device to mac_device. This way, macs can use
it in their log messages.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Acked-by: Camelia Groza <camelia.groza@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>