vboot: refactor OPROM code

The name OPROM is somewhat inaccurate, since other steps to bring
up display and graphics are needed depending on mainboard/SoC.
This patch cleans up OPROM code nomenclature, and works towards
the goal of deprecating vboot1:

* Rename CONFIG_VBOOT_OPROM_MATTERS to
  CONFIG_VBOOT_MUST_REQUEST_DISPLAY and clarify Kconfig
  description
* Remove function vboot_handoff_skip_display_init
* Remove use of the VbInit oflag VB_INIT_OUT_ENABLE_DISPLAY
* Add |flags| field to vboot_working_data struct
* Create VBOOT_FLAG_DISPLAY_REQUESTED and set in vboot_handoff

BUG=b:124141368, b:124192753, chromium:948529
TEST=make clean && make test-abuild
TEST=build and flash eve device; attempt loading dev/rec modes
BRANCH=none

Change-Id: Idf111a533c3953448b4b9084885a9a65a2432a8b
Signed-off-by: Joel Kitching <kitching@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32262
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
diff --git a/src/northbridge/intel/haswell/Kconfig b/src/northbridge/intel/haswell/Kconfig
index 49466bc..8c1e0b1 100644
--- a/src/northbridge/intel/haswell/Kconfig
+++ b/src/northbridge/intel/haswell/Kconfig
@@ -44,7 +44,7 @@
 	  and back to the RW region after the binary is done.
 
 config VBOOT
-	select VBOOT_OPROM_MATTERS
+	select VBOOT_MUST_REQUEST_DISPLAY
 	select VBOOT_STARTS_IN_ROMSTAGE if !HASWELL_VBOOT_IN_BOOTBLOCK
 
 config VGA_BIOS_ID