scsi: megaraid_mbox: Fix spelling of 'allocated'

allocted -> allocated

Link: https://lore.kernel.org/r/20210126054908.45468-1-dingsenjie@163.com


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