scsi: ppa: use new parport device model

Modify ppa driver to use the new parallel port device model.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>