Display network name in status bar

When config_showOperatorNameInStatusBar is true, the network name is
displayed in the status bar.
The user can turn on/off the feature from Settings app (Settings >
Display > Network name).

Fixes: 67620513
Test: manual - insert a valid SIM and go to the Home screen.

Change-Id: I6d03ec00a19e2f5e4c2d2918f1a7c33fdee00dd2