[M] Change in flashrom[main]: libflashrom: Update the API for progress callback

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Peter Marheine, Richard Hughes, Sergii Dmytruk.

Anastasia Klimchuk has posted comments on this change by Anastasia Klimchuk. ( https://review.coreboot.org/c/flashrom/+/86031?usp=email )

Change subject: libflashrom: Update the API for progress callback
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Patch Set 10:

(1 comment)

File include/flash.h:

https://review.coreboot.org/c/flashrom/+/86031/comment/72c2a4ae_37985395?usp... :
PS8, Line 624: 	flashrom_progress_callback_v2 *progress_callback;
             : 	struct flashrom_progress progress_state;
             : 	struct stage_progress stage_progress[FLASHROM_PROGRESS_NR];
             : 	/* deprecated, do not use */
             : 	flashrom_progress_callback *deprecated_progress_callback;
             : 	struct flashrom_progress *deprecated_progress_state;
> That makes sense, but I think that means the old function is currently inconsistent in its behavior  […]

I made an attempt (added lines 90-97 in libflashrom.c), that would ensure only one callback can be registered, whichever one was registered first.

It was not easy to come up with a clear message, but I tried :)

Does this look like something that you meant ?