IDE: Report errors during drive reset back to user space

Make sure that each error condition during the execution of an
HDIO_DRIVE_RESET ioctl is actually reported to the calling process.
Also, unify the exit path of reset_pollfunc() when returning ide_stopped
since the need of ->port_ops->reset_poll() to be treated specially has
vanished (way back, it seems).

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Cc: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
Cc: "Randy Dunlap" <randy.dunlap@oracle.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>