for_each_online_pgdat(): kerneldoc fix

for_each_pgdat() was renamed to for_each_online_pgdat() and kerneldoc
comments should be updated accordingly.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index c463cd8..443bc7c 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -703,7 +703,7 @@
 extern struct zone *next_zone(struct zone *zone);
 
 /**
- * for_each_pgdat - helper macro to iterate over all nodes
+ * for_each_online_pgdat - helper macro to iterate over all online nodes
  * @pgdat - pointer to a pg_data_t variable
  */
 #define for_each_online_pgdat(pgdat)			\