f2fs: add infra for ino management

This patch changes the naming of orphan-related data structures to use as
inode numbers managed globally.
Later, we can use this facility for managing any inode number lists.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 93593ce..f253e22 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1003,7 +1003,7 @@
 	INIT_LIST_HEAD(&sbi->dir_inode_list);
 	spin_lock_init(&sbi->dir_inode_lock);
 
-	init_orphan_info(sbi);
+	init_ino_entry_info(sbi);
 
 	/* setup f2fs internal modules */
 	err = build_segment_manager(sbi);