scsi: fnic: Add support for multiqueue (MQ) in fnic driver

Implement support for MQ in fnic driver:

The block multiqueue layer issues IO to the fnic driver with an MQ tag. Use
the mqtag and derive a tag from it.  Derive the hardware queue from the
mqtag and use it in all paths. Modify queuecommand to handle mqtag.

Replace wq and cq indices to support MQ. Replace the zeroth queue with a
hardware queue.  Implement spin locks on a per hardware queue basis.
Replace io_lock with per hardware queue spinlock.  Implement out of range
tag checks.

Allocate an io_req_table to track status of the io_req.

Test the driver by building it, loading it, and configuring 64 queues in
UCSM. Issue IOs using Medusa on multiple fnics. Enable/disable links to
exercise the abort and clean up path.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310300032.2awCqkfn-lkp@intel.com/


Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Arulprabhu Ponnusamy <arulponn@cisco.com>
Tested-by: Karan Tilak Kumar <kartilak@cisco.com>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
Link: https://lore.kernel.org/r/20231211173617.932990-12-kartilak@cisco.com


Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>