cciss: set rq->errors more correctly in driver

Set rq->errors more correctly in cciss driver.  Previously we had set it
synonymously with the meaning of the last parameter of end_that_last_request
and complete_buffers (the "uptodate" parameter) and had gotten away with it
for all this time because nobody ever looked at rq->errors.
SCSI_IOCTL_SEND_COMMAND looks at rq->errors, so now it matters that it be
right.

Signed-off-by: Stephen M. Cameron <steve.cameron@hp.com>
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>