Fix the values that were off by one.
This was discovered when using postcar stage that prints with
debuglevel BIOS_NEVER.
Change-Id: I73a077950ed0dc735d89c9747a8da0a25f30822d
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/23186
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>