No cell data should re-enable wifi

This CL has 2 parts:
1. plumb cellular availability for the default data SIM from
WifiDataStall to ClientModeImpl
2. Use cellular availability to re-enable networks disabled due to
the user selecting cellular in the provider model.

Bug: 183342311
Bug: 185254813
Test: atest com.android.server.wifi

Change-Id: I45e4dcd6afbcf435df2e2392c61ad96c515c4a7b
12 files changed