fs/erofs: Introduce new features including ztailpacking, fragments and dedupe

This patch updates erofs driver code to catch up with the latest code of
erofs_utils (commit e4939f9eaa177e05d697ace85d8dc283e25dc2ed).

LZMA will be supported in the separate patch later.

Signed-off-by: Yifan Zhao <zhaoyifan@sjtu.edu.cn>
Reviewed-by: Huang Jianan <jnhuang95@gmail.com>