net/mlx5e: Fail attempt to offload e-switch TC encap flows with vlan on underlay

Currently we don't support nor fail attempts to offload encap flows routed
to vlan device on the underlay network. We wrongly consider a vlan underlay
device to be on the same e-switch b/c the switchdev ID is retrieved recursively.

Add explicit check for that and fail such attempts.

Also align to a more strict check for the ingress and the underlay devices
to practically be on the same eswitch.

Fixes: ce99f6b9 ('net/mlx5e: Support SRIOV TC encapsulation offloads for IPv6 tunnels')
Fixes: 3e621b19 ('net/mlx5e: Support TC encapsulation offloads with upper devices')
Signed-off-by: Eli Britstein <elibr@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>