Unit testing proposal

[Jan Dąbroś]

Hi everybody,

Firstly, I want to introduce myself. I'm Jan Dabros and I'm working for
Semihalf - embedded system company based in Poland. I am a big fan of
coreboot and the idea of open firmware in general, that's why would really
like to contribute to this project. Let's see how it goes :)

My proposal is to start unit testing coreboot codebase to some possible
extent, in order to improve its reliability, prepare subsystem for enabling
quick tests and to make test-driven-development possible. Hopefully this
makes sense to (at least some) of you.

For this purpose, it's necessary to select some C unit test framework -
unless we want to create something completely new. I have done evaluation
of couple of such libraries and described its results in the document [1]
along with my selected candidate and implementation proposal. This may be a
good starting point for a discussion about what framework do you think fit
the most and how unit testing may be applied to coreboot codebase.

Together with above doc, I also created a simple example of unit test and
sent it for review [2]. Commit message comprises steps for running it.

Any comments and remarks are very appreciated, both to the doc and the
code. Thanks in advance!

[1] https://review.coreboot.org/c/coreboot/+/39893/1
[2] https://review.coreboot.org/c/coreboot/+/39894/1

Best Regards,
Jan