Migrate to cargo_embargo. am: 34065597a2 am: 78b4caf327 am: d6bfd0ba1f

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/rustc-demangle-capi/+/2832426

Change-Id: I806c13b66076015859e4ccd1290b78bca8c62f31
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>