ide: clear HOB bit for REQ_TYPE_ATA_CMD requests in ide_end_drive_cmd()

ide_dump_status() may set HOB bit before ide_end_drive_cmd() is called.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>