at91_ether: Do not select NET_CORE
This has no dependency on any of the drivers under NET_CORE.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
authored by