qede: Ingress tc flower offload (drop action) support.

The main motive of this patch is to lay down driver's
tc offload infrastructure in place.

With these changes tc can offload various supported flow
profiles (4 tuples, src-ip, dst-ip, l4 port) for the drop
action. Dropped flows statistic is a global counter for
all the offloaded flows for drop action and is populated
in ethtool statistics as common "gft_filter_drop".

Examples -

tc qdisc add dev p4p1 ingress
tc filter add dev p4p1 protocol ipv4 parent ffff: flower \
	skip_sw ip_proto tcp dst_ip 192.168.40.200 action drop
tc filter add dev p4p1 protocol ipv4 parent ffff: flower \
	skip_sw ip_proto udp src_ip 192.168.40.100 action drop
tc filter add dev p4p1 protocol ipv4 parent ffff: flower \
	skip_sw ip_proto tcp src_ip 192.168.40.100 dst_ip 192.168.40.200 \
	src_port 453 dst_port 876 action drop
tc filter add dev p4p1 protocol ipv4 parent ffff: flower \
	skip_sw ip_proto tcp dst_port 98 action drop

Signed-off-by: Manish Chopra <manish.chopra@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>