ide: add ide_set_media_lock() helper

ide: add ide_set_media_lock() helper

* Set IDE_AFLAG_NO_DOORLOCK in idetape_get_mode_sense_result(), check it
  in ide_tape_set_media_lock() and cleanup idetape_create_prevent_cmd().

* Set IDE_AFLAG_NO_DOORLOCK in ide_floppy_create_read_capacity_cmd() and
  check it instead of IDE_AFLAG_CLIK_DRIVE in ide_floppy_set_media_lock().

* Add ide_set_media_lock() helper and convert ide-{floppy,tape}.c to use it.

* Remove no longer used ide*_create_prevent_cmd()/ide*_set_media_lock().

* Update comment in <linux/ide.h> accordingly.

Acked-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>