telephony: Samsung RIL strip off the tailing NITZ data

Samsung added some extra data to the NITZ response that causes the
upper layers to get confused about the data and setting the wrong
timezone. GSMServiceStateTracker would read the last value as timezone
name like it is supplied by the emulator. We strip off these unused data.

Change-Id: I74be270a5c9bfd956183cbe0c56cfd17a357d395