ide: add support for SCSI ioctls to ide-floppy

Now that ide-floppy supports SG_IO we can add support for SCSI ioctls
(except deprecated SCSI_IOCTL_SEND_COMMAND and legacy CDROM_SEND_PACKET
ones - we can add them later iff really needed).

While at it remove handling of CDROMEJECT and CDROMCLOSETRAY ioctls from
generic_ide_ioctl():

- This prevents ide-{disk,tape,scsi} device drivers from obtaining
  REQ_TYPE_BLOCK_PC type requests which are currently unsupported by
  these drivers and which are potentially harmful (as reported by Andrew).

- There is no functionality loss since aforementioned ioctls will now be
  handled by idefloppy_ioctl()->scsi_cmd_ioctl() (for devices using
  ide-floppy driver) and by idecd_ioctl->cdrom_ioctl()->scsi_cmd_ioctl()
  (for devices using ide-cd driver).

Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/ide.c

@@ -1097,10 +1097,6 @@ int generic_ide_ioctl(ide_drive_t *drive, struct file *file, struct block_device
 			return 0;
 		}
 
-		case CDROMEJECT:
-		case CDROMCLOSETRAY:
-			return scsi_cmd_ioctl(file, bdev->bd_disk->queue, bdev->bd_disk, cmd, p);
-
 		case HDIO_GET_BUSSTATE:
 			if (!capable(CAP_SYS_ADMIN))
 				return -EACCES;