octeon_ep: delete unnecessary NULL check

vfree(NULL) is safe. NULL check before vfree() is not needed.
Delete them to simplify the code.
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/octeon_ep/octep_main.c

@@ -980,7 +980,6 @@ static void octep_device_cleanup(struct octep_device *oct)
 	dev_info(&oct->pdev->dev, "Cleaning up Octeon Device ...\n");
 
 	for (i = 0; i < OCTEP_MAX_VF; i++) {
-		if (oct->mbox[i])
 		vfree(oct->mbox[i]);
 		oct->mbox[i] = NULL;
 	}

drivers/net/ethernet/marvell/octeon_ep/octep_rx.c

@@ -230,7 +230,6 @@ static int octep_free_oq(struct octep_oq *oq)
 
 	octep_oq_free_ring_buffers(oq);
 
-	if (oq->buff_info)
 	vfree(oq->buff_info);
 
 	if (oq->desc_ring)

drivers/net/ethernet/marvell/octeon_ep/octep_tx.c

@@ -270,7 +270,6 @@ static void octep_free_iq(struct octep_iq *iq)
 
 	desc_ring_size = OCTEP_IQ_DESC_SIZE * CFG_GET_IQ_NUM_DESC(oct->conf);
 
-	if (iq->buff_info)
 	vfree(iq->buff_info);
 
 	if (iq->desc_ring)