[M] Change in coreboot[main]: mb/hp/(elitebook_820_g2|folio_9480m): Add HP Sure Start workaround

[Arthur Heymans (Code Review)]

Attention is currently required from: Iru Cai, Iru Cai.

Hello Iru Cai, Iru Cai,

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

https://review.coreboot.org/c/coreboot/+/79881?usp=email

to look at the new patch set (#3).

Change subject: mb/hp/(elitebook_820_g2|folio_9480m): Add HP Sure Start workaround
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mb/hp/(elitebook_820_g2|folio_9480m): Add HP Sure Start workaround

To work around HP Sure Start the top of flash needs to contain a vendor
provided image that the EC verifies before releasing the X86 from reset.

Instead of using the wrong flash size and padding the image with dd, add
an fmap layout and use cbfstool memory map arguments to achieve the
same.

UNTESTED.

Signed-off-by: Arthur Heymans 
Change-Id: I0e59d035ce9281062272aeef92f50f2bbf3a9c5f
---
M Documentation/mainboard/hp/elitebook_820_g2.md
M src/mainboard/hp/elitebook_820_g2/Kconfig
M src/mainboard/hp/elitebook_820_g2/Makefile.inc
A src/mainboard/hp/elitebook_820_g2/board.fmd
M src/mainboard/hp/folio_9480m/Kconfig
M src/mainboard/hp/folio_9480m/Makefile.inc
A src/mainboard/hp/folio_9480m/board.fmd
7 files changed, 80 insertions(+), 8 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/81/79881/3