net/mlx4: Use array_size() helper in copy_to_user()

Use array_size() helper instead of the open-coded version in
copy_to_user(). These sorts of multiplication factors need
to be wrapped in array_size().

Link: https://github.com/KSPP/linux/issues/160Signed-off-by: NGustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: NTariq Toukan <tariqt@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/cq.c

@@ -314,7 +314,8 @@ static int mlx4_init_user_cqes(void *buf, int entries, int cqe_size)
 			buf += PAGE_SIZE;
 		}
 	} else {
-		err = copy_to_user((void __user *)buf, init_ents, entries * cqe_size) ?
+		err = copy_to_user((void __user *)buf, init_ents,
+				   array_size(entries, cqe_size)) ?
 			-EFAULT : 0;
 	}