media: ipu3-cio2: Use dma_zalloc_coherent to replace dma_alloc_coherent + memset

dma_zalloc_coherent has implemented the dma_alloc_coherent() + memset(),
We prefer to dma_zalloc_coherent instead of open-codeing.
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/pci/intel/ipu3/ipu3-cio2.c

@@ -218,13 +218,11 @@ static int cio2_fbpt_init(struct cio2_device *cio2, struct cio2_queue *q)
 {
 	struct device *dev = &cio2->pci_dev->dev;
 
-	q->fbpt = dma_alloc_coherent(dev, CIO2_FBPT_SIZE, &q->fbpt_bus_addr,
+	q->fbpt = dma_zalloc_coherent(dev, CIO2_FBPT_SIZE, &q->fbpt_bus_addr,
 				      GFP_KERNEL);
 	if (!q->fbpt)
 		return -ENOMEM;
 
-	memset(q->fbpt, 0, CIO2_FBPT_SIZE);
-
 	return 0;
 }