Regenerate bindgen files and partially automate the process

[pb8o]

Reason for This PR

Fixes #361

Description of Changes

Partially automate the bindings generation process and regenerate them to avoid compiler warnings and errors when upgrading the rust toolchain version.

• [ ] This functionality can be added in rust-vmm.

License Acceptance

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

PR Checklist

[Author TODO: Meet these criteria.] [Reviewer TODO: Verify that these criteria are met. Request changes if not]

• [X] All commits in this PR are signed (git commit -s).
• [X] The issue which led to this PR has a clear conclusion.
• [ ] This PR follows the solution outlined in the related issue.
• [X] The description of changes is clear and encompassing.
• [ ] Any required documentation changes (code and docs) are included in this PR.
• [ ] Any newly added unsafe code is properly documented.
• [ ] Any API changes follow the Runbook for Firecracker API changes.
• [ ] Any user-facing changes are mentioned in CHANGELOG.md.
• [ ] All added/changed functionality is tested.

[JonathanWoollett-Light]

We may be able to avoid having to manually generate these bindings by using https://github.com/rust-vmm/vm-virtio (e.g. specifically https://github.com/rust-vmm/vm-virtio/tree/main/crates/virtio-bindings/src/bindings_v5_0_0), I think the rest of what we manually generate is covered by https://crates.io/crates/libc.

[andreeaflorescu]

We may be able to avoid having to manually generate these bindings by using https://github.com/rust-vmm/vm-virtio (e.g. specifically https://github.com/rust-vmm/vm-virtio/tree/main/crates/virtio-bindings/src/bindings_v5_0_0), I think the rest of what we manually generate is covered by https://crates.io/crates/libc.

We are also going to regenerate the virtio bindings soon using the latest bindgen version which generates safer code. For now, it would be indeed better to just use virtio-bindings from crates.io.