Don't mark an APN disabled if setup fails

We need to leave the phone in a connectable state so that it connects whenever it's able
(reception or just timing).  If we mark it disabled on failure it wont try again.  The retry
comes from the phone layer, not from ConnectivityService.

Also Fix the Phone layer so it retries even if it disconnected by request (DATA_DISABLED).
This was a bug from long ago that didn't become visible until recently with fast wifi and slow
mobile teardown.

Change-Id: I04bf39fba0cb578c87d5fc6ea5d220820ff9f364