[M] Change in coreboot[main]: lib/string: Add strncat() and strcat() functions

[Jakub Czapiga (Code Review)]

Attention is currently required from: Yu-Ping Wu.

Jakub Czapiga has posted comments on this change by Yu-Ping Wu. ( https://review.coreboot.org/c/coreboot/+/83765?usp=email )

Change subject: lib/string: Add strncat() and strcat() functions
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Patch Set 2:

(1 comment)

File tests/lib/string-test.c:

https://review.coreboot.org/c/coreboot/+/83765/comment/45bf3cee_c1afb906?usp... :
PS2, Line 193: ret = strncat(dst, src, len - 1);
`len` is the size of `str` not `src`. This way the case where the count is smaller than src len is not checked. Same is the case for `test_strcat`