net/sched: cls_flower: Support masking for matching on tcp/udp ports

Add the definitions for src/dst udp/tcp port masks and use
them when setting && dumping the relevant keys.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>