chromeos-init: conditionally disable encrypted reboot vault

encrypted-reboot-vault calls RAND_bytes() to create the random
encryption key for the vault. On some devices, this can stall boot
if there isn't enough entropy.

Add a USE flag to disable creation of the encrypted reboot vault.

BUG=b:158580694
TEST=USE=-encrypted_reboot_vault emerge chromeos-init disables
     the encrypted reboot vault.

Cq-Depend: chromium:2419630
Change-Id: I182c13082ec15d75d830e953440505254521c829
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/2419229
Tested-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
Commit-Queue: Sarthak Kukreti <sarthakkukreti@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Aileen Cheng <chengaileen@google.com>
(cherry picked from commit 33c8cac578bb34aa5c0936b73ba7e19122255529)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/2567247
Reviewed-by: Sarthak Kukreti <sarthakkukreti@chromium.org>
Commit-Queue: Shiva Sai Kothapalli <kshivasai@google.com>
Tested-by: Shiva Sai Kothapalli <kshivasai@google.com>
1 file changed