Not to update LocaleOperator if the IMS reg tech is iwlan.

Even if the registration state of PS WLAN is not in-service,
IMS over IWLAN can be registered status. In that case, Changed
localeOperator to null.

Bug: 333346537
Test: atest ServiceStateTrackerTest
Test: Tested under no service + iwlan + wifi ap turn off
Test: basic call, data
Change-Id: I70a98de1d3a36591bea6074b6a53ddddef688d88