Don't toggle app state for updated system apps.

The default carrier app logic to disable/enable apps depending on the
SIM state should only apply to the copy of the app on /system. Once
the app has been updated via /data, we should leave the enabled
setting as the default (though we should still grant carrier
privileges as needed in this case).

Otherwise we may unexpectedly disable a previously enabled app if it
is updated and then the SIM state changes or device reboots at a time
when the SIM isn't loaded.

Bug: 22321187
Change-Id: Ia7281c5a174bd32fc4d63375603ace0b29794894