Before there was a licensing conflict between the keyfile code
(libnm-keyfile) and libnm. The latter would require LGPL-2.1+ while
keyfile code was GPL-2.0+.
Consequently we were linking libnm-keyfile into the daemon, but not in
libnm.so.
This conflict has been resolved and keyfile API is part of libnm.so.
There is no more need to build a separate (intermediary) library. Merge
them.
This also makes sense because keyfile code needs access to private code
from libnm-core. It is closely tied to libnm-core, so that building them
separate makes no sense (anymore).
Currently "src/" mostly contains the source code of the daemon.
I say mostly, because that is not true, there are also the device,
settings, wwan, ppp plugins, the initrd generator, the pppd and dhcp
helper, and probably more.
Also we have source code under libnm-core/, libnm/, clients/, and
shared/ directories. That is all confusing.
We should have one "src" directory, that contains subdirectories. Those
subdirectories should contain individual parts (libraries or
applications), that possibly have dependencies on other subdirectories.
There should be a flat hierarchy of directories under src/, which
contains individual modules.
As the name "src/" is already taken, that prevents any sensible
restructuring of the code.
As a first step, move "src/" to "src/core/". This gives space to
reorganize the code better by moving individual components into "src/".
For inspiration, look at systemd's "src/" directory.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/743
