vboot/vboot_kernel: stop printing keyblock version error when in dev mode

Previously, the "Key version too old." error message is printed
even when in dev mode (!need_keyblock_valid).  Stop printing this
message when the key version check is not applicable.

This CL is part of a series to merge vboot1 and vboot2.0
kernel verification code; see b/181739551.

BUG=b:181739551
TEST=make clean && make runtests
BRANCH=none

Signed-off-by: Joel Kitching <kitching@google.com>
Change-Id: I1c4605342a2c53c45b74be37f2ba597670654a8e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2846252
Tested-by: Joel Kitching <kitching@chromium.org>
Commit-Queue: Joel Kitching <kitching@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
1 file changed