build: Bump log from 0.4.17 to 0.4.20

Bumps [log](https://github.com/rust-lang/log) from 0.4.17 to 0.4.20.
- [Release notes](https://github.com/rust-lang/log/releases)
- [Changelog](https://github.com/rust-lang/log/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/log/compare/0.4.17...0.4.20)

---
updated-dependencies:
- dependency-name: log
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

vm-virtio/Cargo.toml

@@ -8,6 +8,6 @@ edition = "2021"
 default = []
 
 [dependencies]
-log = "0.4.17"
+log = "0.4.20"
 virtio-queue = "0.10.0"
 vm-memory = { version = "0.13.1", features = ["backend-mmap", "backend-atomic", "backend-bitmap"] }