Change in flashrom[master]: tests: add init_shutdown test for realtek_mst_i2c_spi

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Nico Huber, Edward O'Callaghan, Angel Pons, Peter Marheine.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/56911 )

Change subject: tests: add init_shutdown test for realtek_mst_i2c_spi
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Patch Set 4:

(2 comments)

Patchset:

PS4: 
thank you for your work! one comment left :)

File tests/tests.c:

https://review.coreboot.org/c/flashrom/+/56911/comment/2c52b63c_f69ced3c 
PS4, Line 96: return __wrap_open(pathname, flags);
I am sorry I only now noticed this, you don't need to redirect to another wrap, just
`return MOCK_HANDLE;`
If a test wants to have the same logic for open and open64, then that test configures what it wants (defines .open and .open64 to be the same function).