[iwlan] fix deadlock

fix deadlock caused by threads synchronizing on
IwlanDataservice.class and mTunnelStateForApn in opposite order

Also streamline code in setNetworkConnected to avoid excessive
dnsPrefetch calls.

Bug: 194211871
Test: atest and on device wfc/handovers
Change-Id: Iab33824a54a636fe9628188d27299aaa3e757e14
1 file changed