[SCSI] compat: don't perform unneeded copy in sg_io code
The members from 'status' in struct sg_io_hdr to the last are used to
transfer information from kernel to user space. The values that user
space sets are just ignored.
Signed-off-by: Alexey Zaytsev <alexey.zaytsev@gmail.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>