Change in coreboot[master]: mainboard: Drop invalid `VGA_BIOS_FILE` defaults

[Angel Pons (Code Review)]

Attention is currently required from: Nico Huber, Martin Roth, Arthur Heymans, Michael Niewöhner.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51340 )

Change subject: mainboard: Drop invalid `VGA_BIOS_FILE` defaults
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Patch Set 4:

(1 comment)

Patchset:

PS2:
> > As long as the config isn't enabled by default (Which it obviously isn't because if it were, the b […]

For general-purpose users, one could have this in site-local:

default "site-local/mainboard/$(CONFIG_MAINBOARD_DIR)/pci$(CONFIG_VGA_BIOS_ID).rom"

It can be adapted to handle variants as well without much hassle.