Disable auto time zone on non-telephony devices

Disable auto time zone detection explicitly based on device
capabilities.

The TimeZoneDetector now enforces that the time zone cannot be set
manually when "auto_zone" is 1 (on). On devices without a telephony
network (the only devices that support auto time zone currently),
nothing explicitly sets the "auto_zone" value to 0 leading to problems
when the user tries to manually set the time zone. Therefore, to retain
the check, the code needs to ignore the auto_zone setting for devices
that inherently cannot support auto time zone detection.

Bug: 150583524
Bug: 150156441
Test: treehugger
Change-Id: Iea9c9e04c5617ccf0ba20511344884d3d88f2a9b