fs: clarify "dummy" member in struct inodes_stat_t

Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/fs.h

@@ -44,7 +44,7 @@ extern int get_max_files(void);
 struct inodes_stat_t {
 	int nr_inodes;
 	int nr_unused;
-	int dummy[5];
+	int dummy[5];		/* padding for sysctl ABI compatibility */
 };
 extern struct inodes_stat_t inodes_stat;