liquidio: add support for ndo_get_stats64 instead of ndo_get_stats

Support ndo_get_stats64 instead of ndo_get_stats.  Also add stats for
multicast and broadcast packets.

Signed-off-by: Pradeep Nalla <pradeep.nalla@cavium.com>
Acked-by: Raghu Vatsavayi <raghu.vatsavayi@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>