Fixes building vb2lib for postcar. Since postcar is an x86ism, add the
Kconfig options only for x86.
Change-Id: Ib92436bc7270c24689dcf01a47f0c6fe7661814b
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://review.coreboot.org/29395
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>