nfp: abm: enable advanced queuing on demand

ABM NIC FW has a cut-through mode where the PCIe queuing
is bypassed, thus working like our standard NIC FWs.  Use this
mode by default and only enable queuing in switchdev mode where
users can configure it.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>