Disallow data when QNS switched the preference

When the preference has switched to another transport, do
not allow data setup. This avoid the case that data service
keeps asking telephony to retry while QNS already switched
the preference to another transport.

Test: Manual
Fix: 182899920
Fix: 175399007
Merged-In: I1a0c86a978756d5b05851d939e011010f8f1afc2
Change-Id: I1a0c86a978756d5b05851d939e011010f8f1afc2
(cherry picked from commit 50a8fcce)