net/mlx5e: Replace the split logic with extended destination

Currently the FTE encap flag applies to all destinations.
To support mirroring encapsulated traffic to a local port the driver
split the two destinations to two flow table entries:
Table#0: - FWD to the local vport
         - Goto table#1
Table#1: - Encap and FWD to wire
The firmware extended destination capabilities enable the driver to set
an encapsulation flag per destination.

Remove the split logic and use the extended destination mechanism
instead.

Note that split technique is still required for pedit and VLAN push
scenarios.

Signed-off-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>