ide-cd: fix 'ireason' handling for REQ_TYPE_ATA_PC requests

Pass 'struct request *rq' to ide_cd_check_ireason() from cdrom_newpc_intr()
and use ide_cd_check_ireason() also for REQ_TYPE_ATA_PC requests.

This fixes some hangs caused by not finishing the transfer before ending
the request and also makes use of 'ireason == 1' quirk for spurious IRQs.

Tested-by: Brad Rosser <brad.rosser@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>