Upgrade userfaultfd-sys to 0.4.3 am: 29d0edf47f am: 5c1a5fca96 am: c05a4277a0 am: 908d923cde am: edb1c82676

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/userfaultfd-sys/+/2515095

Change-Id: Idc1028c42919d6f56fc15870f448e9cceab4629d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>