Use f2fs_dentry_ptr structure to indicate inline dentry structure as
much as possible, so we can wrap inline dentry with size-fixed fields
to the one with size-changeable fields. With this change, we can
handle size-changeable inline dentry more easily.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>