[M] Change in coreboot[master]: mb/google/rex: Update Rex Flash Layout

[Paul Menzel (Code Review)]

Attention is currently required from: Tarun Tuli, Subrata Banik, Kapil Porwal.

Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74229 )

Change subject: mb/google/rex: Update Rex Flash Layout
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Patch Set 1:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74229/comment/179403b7_a0512033 
PS1, Line 9: This patch updates the Rex flash layout to optimize WP_RO to 4MB.
Why is that done?

https://review.coreboot.org/c/coreboot/+/74229/comment/5cee9331_96a5af93 
PS1, Line 9: This patch updates the Rex flash layout to optimize WP_RO to 4MB.
           : 
           : Changes for chromeos.fmd:
           : 
           : SI_BIOS:
           :      RW_SECTION_A/B: Reduce to 7MB.
           :      RW_LEGACY: Reduce to 1MB.
           :      RW_MISC: Increased to 1MB.
           :      RW_UNUSED: 3MB (reserved)
           :      WP_RO: Reduce to 4MB
           : 
           : Additionally, ensure RW_SECTION_B region starts at 16MB boundary in the
           : SPI Flash.
Why not make it two (or three) commits?

File src/mainboard/google/rex/chromeos.fmd:

https://review.coreboot.org/c/coreboot/+/74229/comment/de15407f_f9bd2f6d 
PS1, Line 7: 7M
I’d make these non-functional changes a separate commit.