project-lakitu: update for new gcc+glibc

- Use /usr/bin/cpp in rpcgen instead of /lib/cpp. /lib/cpp started using
  the CrOS compiler wrapper, and the compiler wrapper doesn't handle the
  /lib/cpp path correctly. /usr/bin/cpp is the right thing to use
  anyway, since that points to the clang preprocessor.
- mask chromeos-base in chromiumos-overlay. COS images want to use
  chromeos-base from project-lakitu.

BUG=b/347026719
TEST=local SDK build, local lakitu{-arm64} builds, presubmit
RELEASE_NOTE=None

Change-Id: Ie2990b20f21da9b5a5e2d7bcbca2b8838c642248
Reviewed-on: https://cos-review.googlesource.com/c/cos/overlays/board-overlays/+/74553
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: He Gao <hegao@google.com>
3 files changed