Setting the Preferred Network Type correctly on SIM restart.

Currently the GsmServiceStateTracker sets the preferred network type to the
last set network type which can cause issues during a SIM swap/reset if the
network type changes. The CdmaServiceStateTracker does not set this value at
all.

This change modifies this behavior to set the preferred network type in the
same manner it is set when a phone reboots.

Change-Id: I88d61a5d545bdbaa4e4400f5f9e4af8f99dc5d2e