ledtrig-network: default missing family to WLAN on non-DT LEDs

For LEDs that have no network trigger configuration in Device Tree
(no mode or family properties), net_activate() infers the family
from the LED name or function string. If that inference fails,
the trigger previously returned -EINVAL and refused to activate.

This is too strict for manual activation via sysfs (e.g.
echo "network" > /sys/class/leds/<led>/trigger) on LEDs that
were not declared for the network trigger in DT. In that case
the user expects the trigger to load with sensible defaults.

Change the non-DT activation path to fall back to NET_TRIG_WLAN
instead of failing, while keeping the condition visible via pr_warn().
Device Tree paths with dt_mode or dt_family are left unchanged
and continue to fail on invalid parameters

Signed-off-by: Mieczyslaw Nalewaj <namiltd@yahoo.com>
Link: https://github.com/openwrt/openwrt/pull/24235
Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>

target/linux/generic/files/drivers/leds/trigger/ledtrig-network.c

@@ -1070,9 +1070,9 @@ static int net_activate(struct led_classdev *led_cdev)
 		 */
 		parsed = parse_family_token(fn, &online);
 		if (parsed < 0) {
-			pr_info("network: unknown function '%s' for LED %s\n",
+			pr_warn("network: cannot infer family from '%s' for LED %s, defaulting to 'wlan'\n",
 				fn ?: "<NULL>", name);
-			return -EINVAL;
+			parsed = NET_TRIG_WLAN;
 		}
 
 		if (online) {