scsi: mpi3mr: Start controller indexing from 0

Instead of displaying the controller index starting from '1' make the
driver display the controller index starting from '0'.

Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Ranjan Kumar <ranjan.kumar@broadcom.com>
Link: https://lore.kernel.org/r/20241110194405.10108-4-ranjan.kumar@broadcom.com


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