Tethering shouldn't indicates on when SIM without tethering option

Before this CL, If SIM doesn't have tethering option then UI will not
back to previous option when press "USB tethering" in
[Default USB configuration].

This CL added receiver to observe USB state that get correct state
from UsbManager.

Bug: 138630479
Test: make -j42 RunSettingsRoboTests
Change-Id: I6cc8da508f6ab142142ca8c28460125bad93925b