infiniband/hw/cxgb4/qp.c: Use dma_zalloc_coherent

Replaced dma_alloc_coherent + memset with dma_zalloc_coherent
Signed-off-by: Sabyasachi Gupta <sabyasachi.linux@gmail.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/cxgb4/qp.c

@@ -2564,13 +2564,12 @@ static int alloc_srq_queue(struct c4iw_srq *srq, struct c4iw_dev_ucontext *uctx,
 	wq->rqt_abs_idx = (wq->rqt_hwaddr - rdev->lldi.vr->rq.start) >>
 		T4_RQT_ENTRY_SHIFT;
 
-	wq->queue = dma_alloc_coherent(&rdev->lldi.pdev->dev,
+	wq->queue = dma_zalloc_coherent(&rdev->lldi.pdev->dev,
 				       wq->memsize, &wq->dma_addr,
 			GFP_KERNEL);
 	if (!wq->queue)
 		goto err_free_rqtpool;
 
-	memset(wq->queue, 0, wq->memsize);
 	dma_unmap_addr_set(wq, mapping, wq->dma_addr);
 
 	wq->bar2_va = c4iw_bar2_addrs(rdev, wq->qid, CXGB4_BAR2_QTYPE_EGRESS,