Change in flashrom[staging]: Give layouts their own type

[Nico Huber (Code Review)]

Hello David Hendricks, build bot (Jenkins),

I'd like you to reexamine a change.  Please visit

https://review.coreboot.org/17944

to look at the new patch set (#5).

Change subject: Give layouts their own type
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Give layouts their own type

Introduce `struct fl_layout` and refactor layout.c a little, so we can
reuse the layout from there and have other sources of layouts beside it.

I didn't want to clutter up flash.h any more. So things went into a new
layout.h.

Change-Id: Icea1a58c283131cc9c5fde6f16d783538dc1a4c7
Signed-off-by: Nico Huber 
---
M flash.h
M layout.c
A layout.h
3 files changed, 102 insertions(+), 50 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/44/17944/5