[SCSI] usb: transport - convert to accessors and !use_sg code path removal

  - This patch depends on:
    usb: transport.c use scsi_eh API in REQUEST_SENSE execution

  - Use scsi data accessors and remove of !use_sg code path.
  - New usb_stor_bulk_srb() for use by drivers

[jejb: updated with corrective fix.

had a bug in residual handling in the new usb_stor_bulk_srb()
function.  Found by Gabriel C. in -mm tree.

Tested-by: Gabriel C <nix.or.die@googlemail.com>
]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Acked-by: Matthew Dharm <mdharm-scsi@one-eyed-alien.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>