mm: bdi init hooks

provide BDI constructor/destructor hooks

[akpm@linux-foundation.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/sysfs/mount.c

@@ -92,6 +92,10 @@ int __init sysfs_init(void)
 	if (!sysfs_dir_cachep)
 		goto out;
 
+	err = sysfs_inode_init();
+	if (err)
+		goto out_err;
+
 	err = register_filesystem(&sysfs_fs_type);
 	if (!err) {
 		sysfs_mount = kern_mount(&sysfs_fs_type);