prototype: Add soc contraint

BUG=None
TEST=None

Change-Id: I8361ee5938a3505292b560a5e37f22d733618542
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/1940304
Reviewed-by: C Shapiro <shapiroc@chromium.org>
Commit-Queue: C Shapiro <shapiroc@chromium.org>
Tested-by: C Shapiro <shapiroc@chromium.org>
Auto-Submit: C Shapiro <shapiroc@chromium.org>
5 files changed