Rename SCSI specific struct and functions to more genenic names.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lin <ming.l@ssi.samsung.com>
Reviewed-by: NSagi Grimberg <sgi@grimberg.me>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>