scsi: megaraid_sas: Send correct PhysArm to FW for R1 VD downgrade

This patch fixes the issue of wrong PhysArm was sent to firmware for R1
VD downgrade.

Signed-off-by: Kiran Kumar Kasturi <kiran-kumar.kasturi@broadcom.com>
Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>