MBB: Handle Captive Portal networks

When a captive portal network is detected, during
MBB, we should:
1. disconnect the old primary CMM
2. make the captive portal CMM primary

Bug: 182926042
Test: atest FrameworksWifiTests
Test: Note: untested on a real captive portal network
Change-Id: I82bed6d6d692405ad2e27565fe3d92d14dd7c950
6 files changed