Merge parts of the tekpower-dmm code (the chip of the TekPower
TP4000ZC seems to be an FS9721_LP3 too) and rework parts of the functions.
Adapt the tekpower-dmm and uni-t-dmm code accordingly.
The Fortune Semiconductor FS9721_LP3 and FS9721B/Q100 DMM chips are very
similar and the protocol looks identical.
Tested on a Voltcraft VC-820 (FS9721_LP3) with the uni-t-dmm driver
(needs some small changes, tbd).
There is no point in libsigrok copying probe lists around. The driver now
builds a list of probes according to the model device it found, and will
make that available to a frontend. The frontend thus has a reference of
what the driver has, including default names, and doesn't need libsigrok
to provide an unnecessary level of abstraction.
The sr_probe_new() library-private function is a helper for drivers.
All frontends will have to include <libsigrok/libsigrok.h> from now on.
This header includes proto.h and version.h, both installed from the
distribution into $INCLUDE/libsigrok/ as well.
The only dynamically changed header is now version.h, which has both
libsigrok and libtool compile-time versions in it.