Enabled when the device supports KEEP FCS and IGNORE FCS.

When the flag is set, pass all received frames up the stack,
even ones with invalid FCS, controlled by ethtool.
Signed-off-by: Muhammad Mahajna <muhammadm@mellanox.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>