sheep: use correct error code in rebae_vdi()

Signed-off-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
sheep: fix vdi clone operation

- pass correct array size
- return FULL_VDI instead of wrong NO_BASE_VDI

Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
sheep: save dw->finish_fd to local variable

We cannot access dw after we call delete_vdis_done() because it may be
already freed.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Reviewed-by: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>