fs: clarify "dummy" member in struct inodes_stat_t

Signed-off-by: Stefan Richter <[e-mail]>
Acked-by: Randy Dunlap <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/linux/fs.h

···
 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;