build: bump vhost from 0c607bb to 9a1aa0b

Bumps [vhost](https://github.com/rust-vmm/vhost) from `0c607bb` to `9a1aa0b`.
- [Release notes](https://github.com/rust-vmm/vhost/releases)
- [Commits](rust-vmm/vhost@0c607bb...9a1aa0b)

---
updated-dependencies:
- dependency-name: vhost
  dependency-type: direct:production
...

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