Problems fixed:

- the sense descriptor is cleared before filling
- BSF and BSFM are added to the commands causing automatic writing of filemark
  if the previous operation was write (tar expects this)
- the block number is set to unknown (-1) if spacing forward ends at BLANK CHECK
- debugging printout of spacing counts fixed to work also with 64-bit systems
Signed-off-by: Kai Makisara <kai.makisara@kolumbus.fi>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>