libdm: Redact keys from dm-crypt targets when calling GetTable. am: c434d801d6 am: 8dce05a18e am: 47bfad8f3c am: 5d784be343

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/29655996

Change-Id: Ib66f2662decdba23eb27189d96f10a6d9222393f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>