[M] Change in flashrom[main]: libflashrom: Added API to enumerate supported programmers

[Peter Marheine (Code Review)]

Attention is currently required from: Dmitry Zhadinets.

Peter Marheine has posted comments on this change by Dmitry Zhadinets. ( https://review.coreboot.org/c/flashrom/+/86921?usp=email )

Change subject: libflashrom: Added API to enumerate supported programmers
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Patch Set 1:

(2 comments)

Patchset:

PS1: 
At least `list_programmers_linebreak` can be converted to use the new API, so it makes sense to do that.

File include/libflashrom.h:

https://review.coreboot.org/c/flashrom/+/86921/comment/305f6656_3d9d7212?usp... :
PS1, Line 169: const char ** flashrom_supported_programmers(void);
I think this would be better avoiding any allocation, by exposing an iterator-like API. I was initially thinking something complex with an opaque iterator type, but then the user would need to call a function to allocate an iterator instance so just exposing an integer ID seems okay.

```
/**
 * Return the name of the programmer with the given ID, starting from 0.
 *
 * Returns NULL if n is larger than the number of available programmers or less
 * than zero.
 */
const char *flashrom_get_programmer_name(int n);
```

A possible downside is that it could be more challenging to support dynamic programmer detection (like if we were to add some kind of plugin architecture) with this API, but it is much easier for users to use this version because there's no dynamic allocation.