ata: sata_nv: Remove call to memset after dmam_alloc_coherent

In commit af7ddd8a
("Merge tag 'dma-mapping-4.21' of git://git.infradead.org/users/hch/dma-mapping"),
dmam_alloc_coherent has already zeroed the memory.
So memset is not needed.
Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/ata/sata_nv.c

@@ -1136,7 +1136,6 @@ static int nv_adma_port_start(struct ata_port *ap)
 				  &mem_dma, GFP_KERNEL);
 	if (!mem)
 		return -ENOMEM;
-	memset(mem, 0, NV_ADMA_PORT_PRIV_DMA_SZ);
 
 	/*
 	 * First item in chunk of DMA memory:
@@ -1946,7 +1945,6 @@ static int nv_swncq_port_start(struct ata_port *ap)
 				      &pp->prd_dma, GFP_KERNEL);
 	if (!pp->prd)
 		return -ENOMEM;
-	memset(pp->prd, 0, ATA_PRD_TBL_SZ * ATA_MAX_QUEUE);
 
 	ap->private_data = pp;
 	pp->sactive_block = ap->ioaddr.scr_addr + 4 * SCR_ACTIVE;