At some point a stray ';' got added into an autotest in a section
of code that is heavily copy pasted. So in turn nearly all the autotests
have this stray ';' after list_devices (and a few in other places).
1) wait for a device to become available
2) add try, except block for the clean termination of iwd in
the case of a failure
3) remove waits
4) eliminate a race condition on get_ordered_networks()
