bmlutils: Fix "Backup/Restore recovery on some devices"

Restoring recovery ($ flash_image recovery) will write recovery also on
the boot partition.
This is because boot and recovery are the same on some samsung phones.
This should be disabled on some samsung phone, in which boot and
recovery are different, in order to restore recovery without overwrite
boot.

Change-Id: Ie96a539806e8e8f0e4fc785b9be5ec02df9c3580