Policy for overlay_remounter

Note - type definitions moved outside the userdebug_or_eng macro to
avoid breaking user builds. User build (lynx-trunk_staging-user) built
and flashed to avoid a repeat of b/392686305

Test: system/core/fs_mgr/tests/adb-remount-test.sh
Bug: 388912628
Change-Id: Ice404a0b798a4dcbfcafb10d5b114807b21dca10
diff --git a/private/vendor_toolbox.te b/private/vendor_toolbox.te
index 178fa8f..5421dd5 100644
--- a/private/vendor_toolbox.te
+++ b/private/vendor_toolbox.te
@@ -7,5 +7,6 @@
         coredomain
         -init
         -modprobe
+        userdebug_or_eng(`-overlay_remounter')
     } vendor_toolbox_exec:file { entrypoint execute execute_no_trans };
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