net: atl*: convert to hw_features

Things left as they were:
 - atl1: is RX checksum really enabled?
 - atl2: copy-paste from atl1, with-errors-on-modify I presume
 - atl1c: there's a bug: MTU can't be changed if device is not up

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>