net: fman: Use mac_dev for some params

Some params are already present in mac_dev. Use them directly instead of
passing them through params.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Acked-by: Camelia Groza <camelia.groza@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>