[S] Change in coreboot[master]: mb/hp/z220_series: Drop VBOOT support

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Felix Singer, Patrick Rudolph, Julius Werner.

Yu-Ping Wu has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/70295 )

Change subject: mb/hp/z220_series: Drop VBOOT support
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Patch Set 2:

(1 comment)

Patchset:

PS2:
> What's the benefit here? I don't understand the problem. […]

The original goal is to deprecate VBOOT_VBNV_CMOS and replace with VBOOT_VBNV_FLASH. However, when I tried to enable VBOOT for HP_Z220_CMT_WORKSTATION (by `select VBOOT` for BOARD_HP_Z220_SERIES_COMMON), the build failed:

E: Image is missing 'GBB' region

The problem is that the board doesn't even have a valid .fmd file for VBOOT. For VBOOT to work the GBB and RW regions must exist. Therefore I just think VBOOT was never supported from the very first.