init: remove unfinished fsverity signature support for APEX sepolicy am: 0b2c5cde1f am: 53e35f410d am: 5518f236e8

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2647684

Change-Id: I0b5adbee8f4e3a255fb51eb145729ca65a6cf6e9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>