dpctl: Properly reflect a rule's offloaded to HW state

dpctl: Properly reflect a rule's offloaded to HW state

Previously, any rule that is offloaded via a netdev, not necessarily
to the HW, would be reported as "offloaded". This patch fixes this
misalignment, and introduces the 'dp' state, as follows:

rule is in HW via TC offload  -> offloaded=yes dp:tc
rule is in not HW over TC DP  -> offloaded=no  dp:tc
rule is in not HW over OVS DP -> offloaded=no  dp:ovs

To achieve this, the flows's 'offloaded' flag was encapsulated in a new
attrs struct, which contains the offloaded state of the flow and the
DP layer the flow is handled in, and instead of setting the flow's
'offloaded' state based solely on the type of dump it was acquired
via, for netdev flows it now sends the new attrs struct to be
collected along with the rest of the flow via the netdev, allowing
it to be set per flow.

For TC offloads, the offloaded state is set based on the 'in_hw' and
'not_in_hw' flags received from the TC as part of the flower. If no
such flag was received, due to lack of kernel support, it defaults
to true.

Signed-off-by: Gavi Teitz <gavi@mellanox.com>
Acked-by: Roi Dayan <roid@mellanox.com>
[simon: resolved conflict in lib/dpctl.man]
Signed-off-by: Simon Horman <simon.horman@netronome.com>