test_platform: Delete deprecated fields

BUG=None
TEST=./generate.sh

Change-Id: I17aa6bb8211ade6ba3659990e6952ae9152c1151
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2567049
Auto-Submit: Prathmesh Prabhu <pprabhu@google.com>
Reviewed-by: Michael Tang <ntang@chromium.org>
Commit-Queue: Michael Tang <ntang@chromium.org>
4 files changed