Change in flashrom[master]: tests: Mock file i/o for linux_mtd and linux_spi tests

[Edward O'Callaghan (Code Review)]

Attention is currently required from: Nico Huber, Angel Pons, Anastasia Klimchuk.
Edward O'Callaghan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/56413 )

Change subject: tests: Mock file i/o for linux_mtd and linux_spi tests
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Patch Set 6:

(2 comments)

File tests/init_shutdown.c:

https://review.coreboot.org/c/flashrom/+/56413/comment/a6a22283_faba909b 
PS6, Line 236: strcpy(
size_t len = min(size*len, strlen(entry.data));
strncpy(buf, entry.data, len);
return len;

https://review.coreboot.org/c/flashrom/+/56413/comment/88300768_6c9b2e9c 
PS6, Line 269: strlen(max_buf_size)
min(len, strlen(max_buf_size))