[Note: This patch is basically a squashed version of the initial driver
commits by Andreas Zschunke <andreas.zschunke@gmx.net>, two fixes by
Andrej Valek <andy@skyrain.eu>, and various coding style / cosmetic
fixes by Uwe Hermann <uwe@hermann-uwe.de> to make the driver a lot more
consistent with the rest of the libsigrok code-base.]