Merge "libc++fs is part of libc++ now." into main am: b6e21e8ebb

Original change: https://android-review.googlesource.com/c/platform/system/security/+/3126253

Change-Id: I70ec83e2bf14a1c83f263ec9f37d1ffe949c5a28
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>