Add warning printks if led_trigger_register_simple() fails.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
 void led_trigger_register_simple(const char *name, struct led_trigger **tp)
 {
        struct led_trigger *trigger;
+       int err;
 
        trigger = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
 
        if (trigger) {
                trigger->name = name;
-               led_trigger_register(trigger);
-       }
+               err = led_trigger_register(trigger);
+               if (err < 0)
+                       printk(KERN_WARNING "LED trigger %s failed to register"
+                               " (%d)\n", name, err);
+       } else
+               printk(KERN_WARNING "LED trigger %s failed to register"
+                       " (no memory)\n", name);
+
        *tp = trigger;
 }