Change in flashrom[master]: dummyflasher: move struct declaration & probe_variable_size to spi.(h|c)

[Anastasia Klimchuk (Code Review)]

Attention is currently required from: Nico Huber, Namyoon Woo, Thomas Heijligen, Edward O'Callaghan.
Anastasia Klimchuk has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/63831 )

Change subject: dummyflasher: move struct declaration & probe_variable_size to spi.(h|c)
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Patch Set 2:

(2 comments)

Patchset:

PS1: 
Oh good, I also didn't want this patch to wait until the code is fixed.
> I think the best is to temporarily move the code as is into a separate file that reflects that there is more to do, e.g. `fixme.c`.

Maybe even `fixme_for_release.c`. The name should be really annoying, so that people want to fix it.

File spi.c:

https://review.coreboot.org/c/flashrom/+/63831/comment/b9177463_14b90289 
PS1, Line 133: int probe_variable_size(struct flashctx *flash)
             : {
             : 	unsigned int i;
             : 	const struct emu_data *emu_data = flash->mst->spi.data;
> > Also it relies on emu_data, what happens if there is some other data in the context? another struc […]

I see. I linked CB:44879 to the bug. It should be fixed, for sure. I am thinking now to take the rest of items (after this patch).