Change in flashrom[master]: Enable dynamic memory allocation checks for cmocka unit tests

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Nico Huber, David Hendricks, Edward O'Callaghan.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/51243 )

Change subject: Enable dynamic memory allocation checks for cmocka unit tests
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Patch Set 6:

(1 comment)

Patchset:

PS6: 
Even better news: now after adding includes in meson.build (my previous patchset) I discovered that unittest.h is not needed anymore in test files! So I am removing it from here. And now ninja test warnings are fixed - because there are no re-definitions anymore.

This looks like a happy ending: only one header, included in build file, no need to touch the code, all files are covered by memory checks when they are built for test environment.

I did all the testing for this last patchset, as before: nm files built for test vs for real, nm test files, running tests. Also introducing memory leak and verifying that test catches it (examples described in commit message).