[PATCH] scsi_ioctl: Add WRITE_LONG_2 as write safe command

Add WRITE_LONG_2 as write safe commands, which which allows normal users to
make a c1-, c2- and cu-scan (so called cxscan) with readcd on
cxscan-capable cd/dvd-writers

Signed-off-by: Jens Axboe <axboe@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>