Squashed 'external/devlib/' changes from 80c0e37d..914a9335

914a9335 host: Fix typo s/src/source
676336a7 target: Use busybox implementation of `kill`
b5cd5358 version: Bump dev version
e6c52c49 version: Bump revision number
6825130e connection: Use busybox implementation of `kill`

git-subtree-dir: external/devlib
git-subtree-split: 914a93355a7c2e7c36c60a910d5c57c47c125a73