scsi: pmcraid: Remove superfluous memset()

Fixes coccicheck warning:

./drivers/scsi/pmcraid.c:4709:3-21: WARNING: dma_alloc_coherent use in pinstance -> hrrq_start [ i ] already zeroes out memory,  so memset is not needed

dma_alloc_coherent() already zeroes out memory so memset() is not needed.

Link: https://lore.kernel.org/r/1596079918-41115-2-git-send-email-liheng40@huawei.comSigned-off-by: Li Heng <liheng40@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/pmcraid.c

@@ -4716,7 +4716,6 @@ static int pmcraid_allocate_host_rrqs(struct pmcraid_instance *pinstance)
 			return -ENOMEM;
 		}
 
-		memset(pinstance->hrrq_start[i], 0, buffer_size);
 		pinstance->hrrq_curr[i] = pinstance->hrrq_start[i];
 		pinstance->hrrq_end[i] =
 			pinstance->hrrq_start[i] + PMCRAID_MAX_CMD - 1;