wilc1000: fix crash observed in AP mode with cfg80211_register_netdevice()

Monitor(mon.) interface is used for handling the AP mode and 'ieee80211_ptr'
reference is not getting set for it. Like earlier implementation,
use register_netdevice() instead of cfg80211_register_netdevice() which
expects valid 'ieee80211_ptr' reference to avoid the possible crash.

Fixes: 2fe8ef10 ("cfg80211: change netdev registration/unregistration semantics")
Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220504161924.2146601-3-ajay.kathat@microchip.com

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

@@ -233,7 +233,7 @@ struct net_device *wilc_wfi_init_mon_interface(struct wilc *wl,
 	wl->monitor_dev->netdev_ops = &wilc_wfi_netdev_ops;
 	wl->monitor_dev->needs_free_netdev = true;
 
-	if (cfg80211_register_netdevice(wl->monitor_dev)) {
+	if (register_netdevice(wl->monitor_dev)) {
 		netdev_err(real_dev, "register_netdevice failed\n");
 		free_netdev(wl->monitor_dev);
 		return NULL;
@@ -251,7 +251,7 @@ void wilc_wfi_deinit_mon_interface(struct wilc *wl, bool rtnl_locked)
 		return;
 
 	if (rtnl_locked)
-		cfg80211_unregister_netdevice(wl->monitor_dev);
+		unregister_netdevice(wl->monitor_dev);
 	else
 		unregister_netdev(wl->monitor_dev);
 	wl->monitor_dev = NULL;