vfs: convert fs_supers to hlist

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e0bc4ff..ed17e54 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1440,7 +1440,7 @@
 	struct block_device	*s_bdev;
 	struct backing_dev_info *s_bdi;
 	struct mtd_info		*s_mtd;
-	struct list_head	s_instances;
+	struct hlist_node	s_instances;
 	struct quota_info	s_dquot;	/* Diskquota specific options */
 
 	int			s_frozen;
@@ -1864,7 +1864,7 @@
 	void (*kill_sb) (struct super_block *);
 	struct module *owner;
 	struct file_system_type * next;
-	struct list_head fs_supers;
+	struct hlist_head fs_supers;
 
 	struct lock_class_key s_lock_key;
 	struct lock_class_key s_umount_key;