We need to convert between protobuf and KVM format of cpuid data in
several places, so let's add helpers to plugin_proto crate.
TEST=cargo test --features plugin; cargo test -p kvm
BUG=chromium:800626
Change-Id: Ida7b59825d2146b0d02711e441f477d90dd4263a
Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/939660
Reviewed-by: Zach Reizner <zachr@chromium.org>