nwztool/scsitools: cleanup and add destination changer tool

Now that we have a nice database of player index, the scsitool becomes more
useful and supports a lot more players. I did some general cleanup of the code,
though eventually it would be nice to really split it into a library and a CLI.
The SCSI vendor command allow to read but also write most NVP nodes. Since there
seems to a demand to change destination and sound pressure settings on device,
I implement this feature in the tool. I do not plan to allow arbitrary NVP
writes because this could easily brick the device. Changing the destination
should be safe, but as usual, use at your own risks.

Change-Id: Iff4e8cc3ac97b965c1df849051c5fd373756cda5
2 files changed