w1: Only wake up the search process if it is going to be searching

It's valid to set the search count to 0 to stop searching, so don't
wake up the search thread to not search.
Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/w1/w1.c

@@ -243,6 +243,8 @@ static ssize_t w1_master_attribute_store_search(struct device * dev,
 	mutex_lock(&md->mutex);
 	md->search_count = tmp;
 	mutex_unlock(&md->mutex);
+	/* Only wake if it is going to be searching. */
+	if (tmp)
 		wake_up_process(md->thread);
 
 	return count;