Upgrade userfaultfd-sys to 0.4.3 am: 29d0edf47f am: 5c1a5fca96

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

Change-Id: I99e569a02765e1ab07ee03859c3e71cb98328e88
Signed-off-by: Automerger Merge Worker <[email protected]>