f2fs: remove unnecessary f2fs_put_page in f2fs_rename

[1] changed the below condition, which made f2fs_put_page() voided.
This patch reapplies the AL's resolution in -next from [2].

-       if (S_ISDIR(old_inode->i_mode)) {
+       if (old_is_dir && old_dir != new_dir) {
                old_dir_entry = f2fs_parent_dir(old_inode, &old_dir_page);
                if (!old_dir_entry) {
                        if (IS_ERR(old_dir_page))

[1] 7deee77b ("f2fs: Avoid reading renamed directory if parent does not change")
[2] https://lore.kernel.org/all/20231220013402.GW1674809@ZenIV/Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/namei.c

@@ -1105,14 +1105,11 @@ static int f2fs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
 		iput(whiteout);
 	}
 
-	if (old_is_dir) {
-		if (old_dir_entry)
-			f2fs_set_link(old_inode, old_dir_entry,
-						old_dir_page, new_dir);
-		else
-			f2fs_put_page(old_dir_page, 0);
+	if (old_dir_entry)
+		f2fs_set_link(old_inode, old_dir_entry, old_dir_page, new_dir);
+	if (old_is_dir)
 		f2fs_i_links_write(old_dir, false);
-	}
+
 	if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_STRICT) {
 		f2fs_add_ino_entry(sbi, new_dir->i_ino, TRANS_DIR_INO);
 		if (S_ISDIR(old_inode->i_mode))