Merge "libc++fs is part of libc++ now." into main am: 94c82c1a5b

Original change: https://android-review.googlesource.com/c/platform/system/vold/+/3113943

Change-Id: I18bb3866041514e1635b7f20e0e6701a546c08ce
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>