[flashrom-gerrit] Change in flashrom[master]: support variable-size SPI chip for dummy programmer

[Namyoon Woo (Code Review)]

Namyoon Woo has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/44879 )

Change subject: support variable-size SPI chip for dummy programmer
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Patch Set 1: Code-Review+1

This is to sync with the one in chromiumos repo.
This patch is quoted from two patches:
- https://codereview.chromium.org/6791015
- https://chromium-review.googlesource.com/c/chromiumos/third_party/flashrom/+...