winrtrunner: Stay attached until the app is terminated

If waiting for the app to terminate, consider the app still running if
it is suspending/suspended. Only stop when the app enters the
terminated state.

Change-Id: I3b56b77dd375fea0ea34e31d60d9a595b3fd7a65
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>