net/mlx5: E-Switch, add ingress rate support

Use the scheduling elements to implement ingress rate limiter on an
eswitch ports ingress traffic. Since the ingress of eswitch port is the
egress of VF port, we control eswitch ingress by controlling VF egress.

Configuration is done using the ports' representor net devices.

Please note that burst size configuration is not supported by devices
ConnectX-5 and earlier generations.

Configuration examples:
tc:
tc filter add dev enp59s0f0_0 root protocol ip matchall action police rate 1mbit burst 20k

ovs:
ovs-vsctl set interface eth0 ingress_policing_rate=1000

Signed-off-by: Eli Cohen <eli@mellanox.com>
Reviewed-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>