Migrate to cargo_embargo. am: f13a18b8e7

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/libloading/+/2838079

Change-Id: I86befac21c9ae2e6cb261203ff83115d0e5bc860
Signed-off-by: Automerger Merge Worker <[email protected]>