submodule: bump openthread from `67c2c04` to `61ecd90` (#278)
submodule: bump openthread from `67c2c04` to `61ecd90` (#278)

Bumps [openthread](https://github.com/openthread/openthread) from `67c2c04` to `61ecd90`.
- [Commits](https://github.com/openthread/openthread/compare/67c2c04f0e615956d39208df0a6acee08a48a154...61ecd9053158ef61b3afca75a8606e237f8cac8f)

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

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
openthread/ot-samr21,openthread/ot-samr21