Enforce core platform hiddenapi checks for Baklava.

This overrides -Xcore-platform-api-policy, which is set from the
persist.debug.dalvik.vm.core_platform_api_policy system property in
app_process.

Test: 674-hiddenapi
Test: Boot and observe "Core platform API enforcement enabled for
      Android 16+" messages from zygote and dex2oat in logcat.
Test: Sideload com.android.art.apex, reboot, and observe that message
      from dex2oat started from odrefresh.
Bug: 377676642
Change-Id: I801d16409bebb8db166a4a5669be27c0d1220343