Two things that need to be noted
- There is no partition type id allocated for squashfs yet. In the
case of sunxi, any non-zero value should work and we keep it 83 (the
value for ext4)
- Remaining spare space within the rootfs partition, not the entire
sdcard space will be formated as either f2fs or ext4 and mounted as
overlay to serve the role of rootfs_data.
Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>