This introduces a new kconfig variable to select the VBNV backing
store explicitly instead of inferring it from CPU/SoC architecture.
x86 platforms have historically relied only on CMOS to store VBNV
variables, while ARM-based platforms have traditionally relied on
the EC. Neither of those solutions are going to scale well into
the future if/when CMOS disappears and we make ARM-based systems
without an EC.
BUG=chrome-os-partner:29546
BRANCH=none
TEST=compiled for nyan_blaze and samus
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Change-Id: I4a8dadfb6bb666baf1ed4bec98b29c145dc4a1e7
Reviewed-on: https://chromium-review.googlesource.com/213877
Reviewed-by: Stefan Reinauer <reinauer@google.com>
Commit-Queue: Vadim Bendebury <vbendeb@chromium.org>
Tested-by: Vadim Bendebury <vbendeb@chromium.org>