usb: device_next: usbd_cdc_ncm: correct net_if_carrier use

net_if_carrier is to be used independently of the
administrative state (start and stop of the ethernet_api).

This way it is no longer wrong. To really make use of it,
net_if_carrier should be changed at the points where a
connection is established or disconnected. But that is
 for later.

Signed-off-by: Fin Maaß <[email protected]>

Author: maass-hamburg

subsys/usb/device_next/class/usbd_cdc_ncm.c

@@ -1123,7 +1123,6 @@ static int cdc_ncm_iface_start(const struct device *dev)
 	LOG_DBG("Start interface %d", net_if_get_by_iface(data->iface));
 
 	atomic_set_bit(&data->state, CDC_NCM_IFACE_UP);
-	net_if_carrier_on(data->iface);
 
 	if (atomic_test_bit(&data->state, CDC_NCM_DATA_IFACE_ENABLED)) {
 		(void)k_work_reschedule(&data->notif_work, K_MSEC(1));
@@ -1158,7 +1157,7 @@ static void cdc_ncm_iface_init(struct net_if *const iface)
 			     sizeof(data->mac_addr),
 			     NET_LINK_ETHERNET);
 
-	net_if_carrier_off(iface);
+	net_if_carrier_on(iface);
 
 	LOG_DBG("CDC NCM interface initialized");
 }