Change in flashrom[master]: libflashrom: Return progress state to the library user

[Edward O'Callaghan (Code Review)]

Attention is currently required from: Richard Hughes, Daniel Campello, Angel Pons, Anastasia Klimchuk, Patrick Rudolph.
Edward O'Callaghan has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/49643 )

Change subject: libflashrom: Return progress state to the library user
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Patch Set 17:

(3 comments)

File include/libflashrom.h:

https://review.coreboot.org/c/flashrom/+/49643/comment/48538fd7_4cfd86d3 
PS17, Line 85: struct flashrom_update_progress *progress_state
> I am a little confused on intended life-times here and why we have two copies of progress_state? We  […]

X: I guess just document this signature better so it is clear why the passed copy is used and not the one in flashctx if there is a reason?

https://review.coreboot.org/c/flashrom/+/49643/comment/8beb72c8_44aa1600 
PS17, Line 97: update
`s/update/set||init/` the func name made me dizzy.

File libflashrom.c:

https://review.coreboot.org/c/flashrom/+/49643/comment/a2db2e8b_58eaa60c 
PS17, Line 84: flashctx->progress_callback(flashctx, flashctx->progress_state);
Y: Because in theory this could become `flashctx->progress_callback(flashctx);` given the above in X.