Add @UnsupportedAppUsage annotations

For packages:
  android.companion

This is an automatically generated CL. See go/UnsupportedAppUsage
for more details.

Exempted-From-Owner-Approval: Mechanical changes to the codebase
which have been approved by Android API council and announced on
android-eng@

Bug: 110868826
Test: m
Change-Id: I10d15bf0f4f0aa4be4f60273bc15d2c075f140e0
Merged-In: Iae49e94fe8cffc1922b5e9cbd0cb9deaeae09b57