scsi: add a symbolic name for the ZBC device type

Make sure we have a symbolic name for the ZBC type available,
so that e.g. patch for a SATA to translate ZAC commands can
make use of it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>