[L] Change in coreboot[main]: Documentation/lib: Update Timestamp documentation

[Nicholas Chin (Code Review)]

Attention is currently required from: Martin L Roth.

Nicholas Chin has posted comments on this change by Martin L Roth. ( https://review.coreboot.org/c/coreboot/+/87186?usp=email )

Change subject: Documentation/lib: Update Timestamp documentation
......................................................................

Patch Set 4:

(1 comment)

File Documentation/lib/timestamp.md:

https://review.coreboot.org/c/coreboot/+/87186/comment/ea50a51a_95863ebc?usp... :
PS4, Line 192: ### Core Functions
> The problem with directly listing functions or structures in the documentation folder is that they w […]

I don't think markdown itself has a way to pull in the header file, though MyST Parser has some wrappers for reStructuredText directives. For example,

```{literalinclude} ../../src/include/timestamp.h
    ```

will include a code block containing that entire file.
https://mystmd.org/guide/code#docs-literalinclude

Parsing out function prototypes and docstrings is something usually associated with something like Doxygen. coreboot used to have a Make target for that, though we dropped support for generating it a while ago; refer to commit 619086d1056c ("Treewide: Remove doxygen config files and targets")
I did find https://breathe.readthedocs.io/en/latest/index.html which seems to be able to bridge doxygen with Sphinx, though I don't know if that's something we want to explore. Not all our docstrings are formatted for Doxygen anyway.