misdn: one handmade ARRAY_SIZE converted

Defined as:

static struct device_attribute element_attributes[] = {
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Karsten Keil <kkeil@suse.de>

drivers/isdn/mISDN/dsp_pipeline.c

@@ -110,8 +110,7 @@ int mISDN_dsp_element_register(struct mISDN_dsp_element *elem)
 	}
 	list_add_tail(&entry->list, &dsp_elements);
 
-	for (i = 0; i < (sizeof(element_attributes)
-		/ sizeof(struct device_attribute)); ++i)
+	for (i = 0; i < ARRAY_SIZE(element_attributes); ++i)
 		ret = device_create_file(&entry->dev,
 				&element_attributes[i]);
 		if (ret) {