Import libfuzzer-sys Rust Crate am: d4c94dacf6 am: 2951b303d0

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/libfuzzer-sys/+/1500710

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I4f350329e875ccbb6b1eda59b80a550ef0bcb5e1