net: fman: Move initialization to mac-specific files

This moves mac-specific initialization to mac-specific files. This will
make it easier to work with individual macs. It will also make it easier
to refactor the initialization to simplify the control flow. No
functional change intended.

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>