framework/target: add get_target_descriptor()
framework/target: add get_target_descriptor()

Add a function to get a TargetDescriptor by its name.

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