Initialize port list in UiccSlotInfo constuctor

UiccSlotInfo.getPorts() assumes a non-null port list. Ensure that the
port list is initialized in the (now deprecated) public constructor. If
it is initialized to null, and getPorts is called, an NPE will occur.

This came up in a setupwizard test that was using the UiccPortInfo
constructor and calling getPorts().

Test: setupwizard SlotsSelectionActivityTest

Bug: 238559684
Bug: 238444812

Change-Id: I0be45f4b55be196f94034f6eb26657202d50e32f