[SCSI] NCR5380 family: convert to accessors & !use_sg cleanup

  - This patch depends on:
      NCR5380: Use scsi_eh API for REQUEST_SENSE invocation
  - convert to accessors and !use_sg cleanup
  - FIXME: Not sg-chain ready look for ++cmd->SCp.buffer

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>