wifi-scripts: netifd: fix null dereference in config_init for missing devices

Add optional chaining when accessing device config in the wifi-iface
loop to handle cases where a referenced device doesn't exist.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
(cherry picked from commit ebd2fefea5152d032cded1ccc7cf6e731b5bbcc2)

Author: nbd168

package/network/config/wifi-scripts/files/lib/netifd/wireless.uc

@@ -165,7 +165,7 @@ function config_init(uci)
 		let mlo_vif = parse_bool(data.mlo);
 		let radios = map(dev_names, (v) => radio_idx[v]);
 		radios = filter(radios, (v) => v != null);
-		let radio_config = map(dev_names, (v) => devices[v].config);
+		let radio_config = map(dev_names, (v) => devices[v]?.config);
 		let ifname;
 		let mlo_created = false;