vboot: Change oprom checks to CONFIG_VBOOT, assert OPROM_MATTERS

Skipping display init on normal-mode boot is a vboot feature, not
specific to Chrome OS. Fix the code in display_init_required() and
pci_dev_init() to check CONFIG_VBOOT rather than CONFIG_CHROMEOS now
that the two aren't always the same anymore.

Also add a check to guarantee at compile time that
CONFIG_VBOOT_OPROM_MATTERS is enabled on all platforms that make a check
to this function (when CONFIG_VBOOT is also enabled). The whole display
skipping mechanism is based on the oprom_needed NVRAM flag, and skipping
display init without enabling the option to tell vboot that it needs to
pay attention to that flag would make the whole thing not work right.

Change-Id: I5d6421509bdcdaa61b78015af3fa6241fe75bb7f
Signed-off-by: Julius Werner <jwerner@chromium.org>
---
M src/device/pci_device.c
M src/lib/bootmode.c
2 files changed, 8 insertions(+), 3 deletions(-)