Fix confusing opal debug messages

Previously we passed ioctl return code to general error translatation function. This was wrong since ioctl always returns -1 on error.

Also let's not print sed-opal specific error debug messages if the sed-opal ioctl was not even passed to sed-opal kernel iface and failed earlier (e.g.: sed-opal iface was not configured during kernel compilation or specific iocl command number is not implemented in current kernel)