[dfu-util] New dfu-suffix manipulation tool

[Stefan Schmidt]

Hello Tormod and others.

One major feature we lacked from the beginning was support for the DFU
suffix manipulation. Tormad added parsing support some time ago and
now I finally found some time to finish a small stand alone
manipulation tool for DFU suffices.

Nothing big, the suffix itself is small, but finally a way to add a
suffix to existing fimrware files and allow dfu-util to verify the
firmware against corruption (CRC) or wrong usage (USB product and
vendor ids).

It allows to verify, remove and add a suffix to a given file:

Verify:
dfu-suffix -c $FILE

Remove:
dfu-suffix -D $FILE

Add:
dfu-suffix -a $FILE -d 0x1000 -p 0x92AD -v 0x403

Values for device, product and vendor id can be in decimal or hex
notation. Later needs a 0x prefix.

@Tormod: I haven't applied the code to the master branch yet. Would be
glad if you could give it a fast review before I do this:

http://cgit.openezx.org/dfu-util/commit/?h=dfu-suffix&id=15757085aa10294b9a58719a42e922fe30405ff8
http://cgit.openezx.org/dfu-util/commit/?h=dfu-suffix&id=f77d394e98f790efef043f4eec88c9bd2dde06eb

Once this is in and no problems show up I would want to go for a 0.6
release. If you, or anyone else, has some fixes around let me know.

For the next release cycle I would like to see how we can integrate
the windows support Satz Klauer wrote.

regards
Stefan Schmidt