Allow TPM to log events in a circular buffer through tpm_log_event().
Logs can be retrieved through a new vendor command
VENDOR_CC_POP_LOG_ENTRY.
BUG=b:63760920
TEST=On eve, store TPM logs through 'logentry' cr50 console command,
verify logs are fetched correctly through 'trunks_send --pop_logentry'.
BRANCH=None
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Change-Id: Idbc405728c0ba68078447fb59717d6115830e3d8
Reviewed-on: https://chromium-review.googlesource.com/599352
Commit-Ready: Shawn N <shawnn@chromium.org>
Tested-by: Shawn N <shawnn@chromium.org>
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
