IB/mlx4: Convert kmalloc to kmalloc_array for checkpatch

Convert kmalloc to be kmalloc_array to fix warnings below:

WARNING: Prefer kmalloc_array over kmalloc with multiply
+               qp->sq.wrid = kmalloc(qp->sq.wqe_cnt * sizeof(u64),

WARNING: Prefer kmalloc_array over kmalloc with multiply
+               qp->rq.wrid = kmalloc(qp->rq.wqe_cnt * sizeof(u64),

WARNING: Prefer kmalloc_array over kmalloc with multiply
+               srq->wrid = kmalloc(srq->msrq.max * sizeof(u64),

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/mlx4/srq.c b/drivers/infiniband/hw/mlx4/srq.c
index f416c74..68d5a5f 100644
--- a/drivers/infiniband/hw/mlx4/srq.c
+++ b/drivers/infiniband/hw/mlx4/srq.c
@@ -171,7 +171,7 @@
 		if (err)
 			goto err_mtt;
 
-		srq->wrid = kmalloc(srq->msrq.max * sizeof(u64),
+		srq->wrid = kmalloc_array(srq->msrq.max, sizeof(u64),
 					GFP_KERNEL | __GFP_NOWARN);
 		if (!srq->wrid) {
 			srq->wrid = __vmalloc(srq->msrq.max * sizeof(u64),