mediatek: leds-smartrg: propagate i2c errors from blink_set

srg_led_set_pulse() returns !cbyte regardless of whether the i2c
writes succeeded, reporting successful pattern offload for a
failed bus transaction. Return the i2c error instead; a non-zero
return makes the LED core fall back to software blinking, which
recovers the pattern once the bus is healthy again.

Signed-off-by: Chad Monroe <chad@monroe.io>
Link: https://github.com/openwrt/openwrt/pull/24354
Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>

target/linux/mediatek/files/drivers/leds/leds-smartrg-system.c

@@ -89,7 +89,10 @@ srg_led_set_pulse(struct led_classdev *led_cdev,
 	}
 	mutex_unlock(&sysled_ctrl->lock);
 
-	return !cbyte;
+	if (ret)
+		return ret;
+
+	return cbyte ? 0 : 1;
 }
 
 static int