net: axienet: Utilize of_get_mac_address()

Do not open code getting the MAC address exclusively from the
"local-mac-address" property, but instead use of_get_mac_address()
which looks up the MAC address using the 3 typical property names.

Also avoid casting away the const qualifier of the return value by
making axienet_set_mac_address() take a const void* address.

Follows commit b34296a9c047 ("net: ethoc: Utilize
of_get_mac_address()").

Cc: Florian Fainelli <[e-mail]>
Signed-off-by: Tobias Klauser <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/ethernet/xilinx/xilinx_axienet_main.c

···
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/of_mdio.h>
+#include <linux/of_net.h>
 #include <linux/of_platform.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
···
  * This function is called to initialize the MAC address of the Axi Ethernet
  * core. It writes to the UAW0 and UAW1 registers of the core.
  */
-static void axienet_set_mac_address(struct net_device *ndev, void *address)
+static void axienet_set_mac_address(struct net_device *ndev,
+				    const void *address)
 {
 	struct axienet_local *lp = netdev_priv(ndev);
 
···
 	struct device_node *np;
 	struct axienet_local *lp;
 	struct net_device *ndev;
-	u8 mac_addr[6];
+	const void *mac_addr;
 	struct resource *ethres, dmares;
 	u32 value;
 
···
 	}
 
 	/* Retrieve the MAC address */
-	ret = of_property_read_u8_array(pdev->dev.of_node,
-					"local-mac-address", mac_addr, 6);
-	if (ret) {
+	mac_addr = of_get_mac_address(pdev->dev.of_node);
+	if (!mac_addr) {
 		dev_err(&pdev->dev, "could not find MAC address\n");
 		goto free_netdev;
 	}
-	axienet_set_mac_address(ndev, (void *)mac_addr);
+	axienet_set_mac_address(ndev, mac_addr);
 
 	lp->coalesce_count_rx = XAXIDMA_DFT_RX_THRESHOLD;
 	lp->coalesce_count_tx = XAXIDMA_DFT_TX_THRESHOLD;