net/mlx5: HWS, added actions handling

When a packet matches a flow, the actions specified for the flow are
applied. The supported actions include (but not limited to) the following:
 - drop: packet processing is stopped
 - go to vport: packet is forwarded to a specified vport
 - go to flow table: packet is forwarded to a specified table
   and processing continues there
 - push/pop vlan: add/remove vlan header respectively to/from the packet
 - insert/remove header: add/remove a user-defined header to/from
   the packet
 - counter: count the packet bytes in the specified counter
 - tag: tag the matching flow with a provided tag value
 - reformat: change the packet format by adding or removing some
   of its headers
 - modify header: modify the value of the packet headers with
   set/add/copy ops
 - range: match packet on range of values

Reviewed-by: Erez Shitrit <erezsh@nvidia.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Author: kliteyn