submodule: bump openthread from 30aa3e8 to d0f6d17 (#721)

Bumps [openthread](https://github.com/openthread/openthread) from `30aa3e8` to `d0f6d17`.
- [Commits](openthread/openthread@30aa3e8...d0f6d17)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]