Add support for auditable Rust binaries

[tofay]

What would you like to be added:
rust-audit is a tool/cargo plugin for embedding dependency information in Rust binaries, for subsequent scanning/inspection (similar to go binaries).

I'd like syft to be able to detect Rust crate dependencies in Rust binaries built with rust

Why is this needed:
To account for statically linked Rust binaries in SBOMs/scanning.

Additional context:
I've been discussing rust-audit with the Rust secure code working group recently - the format is currently a simplified version of Cargo.lock but there's a desire to embed the information in a standardized way and we're looking into options.
Because of this if syft were to support this it should likely be marked as experimental, or off by default in some way.