[XS] Change in coreboot[main]: Disable separate romstage for emulation builds

[Simon Glass (Code Review)]

Attention is currently required from: Angel Pons, Arthur Heymans, Simon Glass.

Simon Glass has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79079?usp=email )

Change subject: Disable separate romstage for emulation builds
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Patch Set 3:

(1 comment)

File src/Kconfig:

https://review.coreboot.org/c/coreboot/+/79079/comment/db652a60_9ad8433f :
PS3, Line 248: 	default y if !VENDOR_EMULATION
> Can you override the default value for `SEPARATE_ROMSTAGE` from `src/mainboard/emulation/` instead?  […]

Do you know how to do that? So far as I can tell a 'default n' does not override a 'default y' but perhaps it depends on the ordering/

This is what I tried in src/mainboard/emulation/Kconfig :

config SEPARATE_ROMSTAGE
    default n