selftests: mlxsw: egress_vid_classification: Fix the diagram

The topology diagram implies that $swp1 and $swp2 are members of the bridge
br0, when in fact only their uppers, $swp1.10 and $swp2.10 are. Adjust the
diagram.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Amit Cohen <amcohen@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mlxsw: Add egress VID classification test

After routing, the device always consults a table that determines the
packet's egress VID based on {egress RIF, egress local port}. In the
unified bridge model, it is up to software to maintain this table via
REIV register.

The table needs to be updated in the following flows:
1. When a RIF is set on a FID, for each FID's {Port, VID} mapping, a new
{RIF, Port}->VID mapping should be created.
2. When a {Port, VID} is mapped to a FID and the FID already has a RIF,
a new {RIF, Port}->VID mapping should be created.

Add a test to verify that packets get the correct VID after routing,
regardless of the order of the configuration.

# ./egress_vid_classification.sh
TEST: Add RIF for existing {port, VID}->FID mapping [ OK ]
TEST: Add {port, VID}->FID mapping for FID with a RIF [ OK ]

Signed-off-by: Amit Cohen <amcohen@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>