lakitu, lakitu-arm64: Add virtual/target-os

We want project-lakitu to be a library overlay, and not a board overlay
(i.e. it cannot be used to create images). To this end, we want to
remove virtual/target-os from project-lakitu, and define this package in
all board overlays.

To accomplish this, we first define virtual/target-os in all board
overlays. Then we will remove virtual/target-os from project-lakitu.
This change defines virtual/target-os for lakitu and lakitu-arm64.

BUG=b/173144094
TEST=presubmit
RELEASE_NOTE=None

Change-Id: I5930edb51746d02aace49164cdd096a35aedc614
Reviewed-on: https://cos-review.googlesource.com/c/cos/overlays/board-overlays/+/9961
Reviewed-by: Edward Jee <edjee@google.com>
Reviewed-by: Roy Yang <royyang@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
4 files changed