vboot: fix legacy_clamshell_tests when PHYSICAL_PRESENCE_KEYBOARD=1

Physical presence checks in VbUserConfirms are only invoked
when PHYSICAL_PRESENCE_KEYBOARD=0.  Disable these tests when
PHYSICAL_PRESENCE_KEYBOARD=1.

BUG=chromium:943150
TEST=PHYSICAL_PRESENCE_KEYBOARD=0 make runtests
TEST=PHYSICAL_PRESENCE_KEYBOARD=1 make runtests
BRANCH=none

Signed-off-by: Joel Kitching <kitching@google.com>
Change-Id: I0c32913549a856855918c54378e5d265851abe37
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2237086
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
Commit-Queue: Joel Kitching <kitching@chromium.org>
Tested-by: Joel Kitching <kitching@chromium.org>
1 file changed