Change in coreboot[master]: tests: code coverage improvements

[Jakub Czapiga (Code Review)]

Attention is currently required from: Paul Fagerburg, Julius Werner.
Jakub Czapiga has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54072 )

Change subject: tests: code coverage improvements
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Patch Set 3: Code-Review+2

(2 comments)

File tests/Makefile.inc:

https://review.coreboot.org/c/coreboot/+/54072/comment/6710dfc5_c141bee7 
PS3, Line 199: coverage_rpt
nit: "coveratge_reports" might be better, but it's just my taste.

https://review.coreboot.org/c/coreboot/+/54072/comment/ebb947ee_f31dcff8 
PS3, Line 258: @echo  '  clean-coverage-report-tests'
             : 	@echo  '                        - Remove the code coverage report'
nit: You can reformat this whole section to make all target names and their first line of description to fit in one line. It won't be bigger than 80 characters but will increase readability :)