scsi: mvsas: Remove superfluous memset()

Fixes coccicheck warning:

./drivers/scsi/mvsas/mv_init.c:244:11-29: WARNING: dma_alloc_coherent use in mvi -> tx already zeroes out memory,  so memset is not needed
./drivers/scsi/mvsas/mv_init.c:250:15-33: WARNING: dma_alloc_coherent use in mvi -> rx_fis already zeroes out memory,  so memset is not needed
./drivers/scsi/mvsas/mv_init.c:256:11-29: WARNING: dma_alloc_coherent use in mvi -> rx already zeroes out memory,  so memset is not needed
./drivers/scsi/mvsas/mv_init.c:265:13-31: WARNING: dma_alloc_coherent use in mvi -> slot 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/1596078235-54002-1-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/mvsas/mv_init.c

@@ -246,19 +246,16 @@ static int mvs_alloc(struct mvs_info *mvi, struct Scsi_Host *shost)
 				     &mvi->tx_dma, GFP_KERNEL);
 	if (!mvi->tx)
 		goto err_out;
-	memset(mvi->tx, 0, sizeof(*mvi->tx) * MVS_CHIP_SLOT_SZ);
 	mvi->rx_fis = dma_alloc_coherent(mvi->dev, MVS_RX_FISL_SZ,
 					 &mvi->rx_fis_dma, GFP_KERNEL);
 	if (!mvi->rx_fis)
 		goto err_out;
-	memset(mvi->rx_fis, 0, MVS_RX_FISL_SZ);
 
 	mvi->rx = dma_alloc_coherent(mvi->dev,
 				     sizeof(*mvi->rx) * (MVS_RX_RING_SZ + 1),
 				     &mvi->rx_dma, GFP_KERNEL);
 	if (!mvi->rx)
 		goto err_out;
-	memset(mvi->rx, 0, sizeof(*mvi->rx) * (MVS_RX_RING_SZ + 1));
 	mvi->rx[0] = cpu_to_le32(0xfff);
 	mvi->rx_cons = 0xfff;
 
@@ -267,7 +264,6 @@ static int mvs_alloc(struct mvs_info *mvi, struct Scsi_Host *shost)
 				       &mvi->slot_dma, GFP_KERNEL);
 	if (!mvi->slot)
 		goto err_out;
-	memset(mvi->slot, 0, sizeof(*mvi->slot) * slot_nr);
 
 	mvi->bulk_buffer = dma_alloc_coherent(mvi->dev,
 				       TRASH_BUCKET_SIZE,