[M] Change in flashrom[master]: tests: Add llvm-cov option and run target for code coverage

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Thomas Heijligen, Evan Benn.

Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/69268 )

Change subject: tests: Add llvm-cov option and run target for code coverage
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Patch Set 14:

(2 comments)

Commit Message:

https://review.coreboot.org/c/flashrom/+/69268/comment/504779e2_6690f6b8 
PS11, Line 14: TEST=meson test; ninja llvm-cov-tests
> I ran it for all the test_build configs with coverage enabled, anad with and without tests.

I meant to say, test scenario == "build flashrom and run tests with coverage disabled"
(from your comment & commit message it sounds like you always run with coverage enabled)

File meson.build:

https://review.coreboot.org/c/flashrom/+/69268/comment/0050fe45_d70391e3 
PS14, Line 625: run_target('llvm-cov-cli', command : ['scripts/llvm-cov', classic_cli])
But why this is always run? It should only run when feature is enabled?