Remove 5s sleep on partial messages
Remove 5s sleep on partial messages

RVI_ERR_JSON_PART isn't actually an error: it means that we should call
rviProcessInput again.

advancedtelematic/aktualizr,advancedtelematic/aktualizr,advancedtelematic/aktualizr,advancedtelematic/sota_client_cpp,advancedtelematic/sota_client_cpp,advancedtelematic/aktualizr