scsi: cxlflash: Support image reload policy modification

On a PERST, the AFU image can be reloaded or left intact. Provide means to set
this image reload policy.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>