Initialize userfaultfd availability even when not using it am: 6c6e2df516 am: 409f480fdb

Original change: https://android-review.googlesource.com/c/platform/art/+/2402134

Change-Id: I09d75b8da4be6bc304b203d70017e8662c91083e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>