workloads: Add manual workload
workloads: Add manual workload

Port manual workload from WA2. This workload allows using WA to
configure and instrument the target, while letting the user perform
arbitrary actions in place of running a fixed workload.

setrofim/workload-automation,setrofim/workload-automation,lisatn/workload-automation,ARM-software/workload-automation,lisatn/workload-automation,lisatn/workload-automation,lisatn/workload-automation,ARM-software/workload-automation,ARM-software/workload-automation,ARM-software/workload-automation,setrofim/workload-automation,setrofim/workload-automation