scsi: mpi3mr: Add support for internal watchdog thread

The watchdog thread is the driver's internal thread which does a few things
such as detecting firmware faults, resetting the controller, performing
timestamp sync, etc.

Link: https://lore.kernel.org/r/20210520152545.2710479-6-kashyap.desai@broadcom.com


Cc: sathya.prakash@broadcom.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>