wifi: wilc1000: set wilc_set_mac_address parameter as const

Any attempt to provide a const mac address to wilc_set_mac_address results
in the following warning:

warning: passing argument 2 of 'wilc_set_mac_address' discards 'const'
qualifier from pointer target type [-Wdiscarded-qualifiers]
[...]
drivers/net/wireless/microchip/wilc1000/hif.h:170:52: note: expected 'u8 *'
{aka 'unsigned char *'} but argument is of type 'const unsigned char *'a
int wilc_set_mac_address(struct wilc_vif *vif, u8 *mac_addr);

Instead of using an explicit cast each time we need provide a MAC address,
set the function parameter as const
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240514-mac_addr_at_probe-v2-3-afef09f1cd10@bootlin.com

drivers/net/wireless/microchip/wilc1000/hif.c

@@ -1293,7 +1293,7 @@ int wilc_get_mac_address(struct wilc_vif *vif, u8 *mac_addr)
 	return result;
 }
 
-int wilc_set_mac_address(struct wilc_vif *vif, u8 *mac_addr)
+int wilc_set_mac_address(struct wilc_vif *vif, const u8 *mac_addr)
 {
 	struct wid wid;
 	int result;
@@ -1301,7 +1301,7 @@ int wilc_set_mac_address(struct wilc_vif *vif, u8 *mac_addr)
 	wid.id = WID_MAC_ADDR;
 	wid.type = WID_STR;
 	wid.size = ETH_ALEN;
-	wid.val = mac_addr;
+	wid.val = (u8 *)mac_addr;
 
 	result = wilc_send_config_pkt(vif, WILC_SET_CFG, &wid, 1);
 	if (result)

drivers/net/wireless/microchip/wilc1000/hif.h

@@ -167,7 +167,7 @@ int wilc_add_rx_gtk(struct wilc_vif *vif, const u8 *rx_gtk, u8 gtk_key_len,
 		    u8 cipher_mode);
 int wilc_set_pmkid_info(struct wilc_vif *vif, struct wilc_pmkid_attr *pmkid);
 int wilc_get_mac_address(struct wilc_vif *vif, u8 *mac_addr);
-int wilc_set_mac_address(struct wilc_vif *vif, u8 *mac_addr);
+int wilc_set_mac_address(struct wilc_vif *vif, const u8 *mac_addr);
 int wilc_set_join_req(struct wilc_vif *vif, u8 *bssid, const u8 *ies,
 		      size_t ies_len);
 int wilc_disconnect(struct wilc_vif *vif);

drivers/net/wireless/microchip/wilc1000/netdev.c

@@ -678,7 +678,7 @@ static int wilc_set_mac_addr(struct net_device *dev, void *p)
 	}
 	rcu_read_unlock();
 
-	result = wilc_set_mac_address(vif, (u8 *)addr->sa_data);
+	result = wilc_set_mac_address(vif, addr->sa_data);
 	if (result)
 		return result;