mlxsw: Add support for 802.1Q FID family

mlxsw: Add support for 802.1Q FID family

Using the legacy bridge model, there is no VID classification at egress
for 802.1Q FIDs, which means that the VID is maintained.

This behavior cause the limitation that 802.1Q FIDs cannot work with VXLAN.
This limitation stems from the fact that a decapsulated VXLAN packet should
not contain a VLAN tag. If such a packet was to egress from a local port
using a 802.1Q FID, it would "maintain" its VLAN on egress, which is no
VLAN at all.

Currently 802.1Q FIDs are emulated in mlxsw driver using 802.1D FIDs. Using
unified bridge model, there is a FID->VID mapping, so it is possible to
stop emulating 802.1Q FIDs.

The main changes are:
1. Use 'SFGC.bridge_type' = 0, to separate between 802.1Q FIDs and
   802.1D FIDs.
2. Use VLAN RIF instead of the emulated one (VLAN_EMU which is emulated
   using FID RIF).
3. Create VID->FID mapping when the FID is created. Then when a new port
   is mapped to the FID, if it not in virtual mode, no new mapping is
   needed. Save the new port in 'port_vid_list', to be able to update a
   RIF in all {Port, VID}->FID mappings in case that the port will be in
   virtual mode later.
4. Add a dedicated operation function per FID family to update RIF for
   VID->FID mappings. For 802.1d and rFID families, just return. For
   802.1q family, handle the global mapping which is created for new 802.1q
   FID.

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