scsi: smartpqi: Update device removal management

scsi: smartpqi: Update device removal management

Update device removal path to handle issues for:

 - rmmod: Correct stack trace when removing devices.
 - rmmod: Synchronize SCSI cache.
 - Update handling for removing devices using sysfs.

Link: https://lore.kernel.org/r/20210928235442.201875-2-don.brace@microchip.com
Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Acked-by: John Donnelly <john.p.donnelly@oracle.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>