REQ_DRIVE_TASKFILE requests aren't retried so don't clear rq->errors
in CONFIG_IDE_TASKFILE_IO=n PIO handlers and in CONFIG_IDE_TASKFILE_IO=y
PIO handlers clear rq->errors only for fs requests, flagged_* PIO
handlers were already okay.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>