Steps to reproduce:

  # mkfs.btrfs /dev/sda2
  # mount /dev/sda2 /mnt
  # touch /mnt/file0
  # setfacl -m 'u:root:x,g::x,o::x' /mnt/file0
  # umount /mnt
  # mount /dev/sda2 -o noacl /mnt
  # getfacl /mnt/file0
  ...
  user::rw-
  user:root:--x
  group::--x
  mask::--x
  other::--x

The output should be:

  user::rw-
  group::--x
  other::--x
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>