submodule: bump openthread from `bfb6020` to `40484c9` (#276)
submodule: bump openthread from `bfb6020` to `40484c9` (#276)

Bumps [openthread](https://github.com/openthread/openthread) from `bfb6020` to `40484c9`.
- [Commits](https://github.com/openthread/openthread/compare/bfb60204fcb27dc874685b63049be249ac7ddb08...40484c94687163e60e44e3f23855b49e7dd911df)

---
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-nxp,openthread/ot-nxp,openthread/ot-nxp