Migrate to cargo_embargo. am: 6dbb08787b

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/userfaultfd-sys/+/2835512

Change-Id: Ic2af27302d96d8d03b2204e7fa26360589b41092
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>