mlxsw: spectrum_nve: Un/offload FDB on nve_fid_disable/enable

Any existing NVE FDB entries need to be offloaded when NVE is enabled
for a given FID. Recent patches have added fdb_replay op for this, so
just invoke it from mlxsw_sp_nve_fid_enable().

When NVE is disabled on a FID, any existing FDB offloaded marks need to
be cleared on NVE device as well as on its bridge master. An op to
handle this, fdb_clear_offload, has been added to FID ops and NVE ops in
previous patches. Add code to resolve the NVE device, NVE type, and
dispatch to both fdb_clear_offload ops.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>