Change in coreboot[master]: tests: Add lib/spd_cache-test test case

[Jakub Czapiga (Code Review)]

Attention is currently required from: Paul Fagerburg, Jan Dabros.
Jakub Czapiga has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52938 )

Change subject: tests: Add lib/spd_cache-test test case
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Patch Set 3:

(2 comments)

File tests/include/tests/lib/spd_cache_data.h:

https://review.coreboot.org/c/coreboot/+/52938/comment/ba8966f9_d9da15a5 
PS2, Line 5: unsigned char spd_data_ddr4_1[] = {
> For the record: […]

Done

File tests/lib/spd_cache-test.c:

https://review.coreboot.org/c/coreboot/+/52938/comment/eac2edcf_65cd8b93 
PS2, Line 50: static void test_load_spd_cache(void **state)
> Yes, this requires some explanation. I will add it in next version.

Done