Revert "Make sure to kill potential sub-process on command exec."
Revert "Make sure to kill potential sub-process on command exec."

This reverts commit 3c7fc35906597adfc83b47b457512cb025c0c91f.

The reason for reverting is that this solution can't be cross-compiled
as it is specific to Linux.

brocaar/lora-gateway-bridge,brocaar/lora-semtech-bridge,brocaar/lora-gateway-bridge,brocaar/lora-semtech-bridge