Supported the legacy allowed initial attach APN types config

Some carriers requires user-added APNs to be used for initial
attach, but IA was automatically removed by the APN editor on
purpose. So the compromised solution was supporting the old
allowed IA APN types carrier config in the new data stack.

Fix: 216867081
Test: Manual
Change-Id: If3acbe92ed25d254c61947c4535e2bdc2613d7b7
Merged-In: If3acbe92ed25d254c61947c4535e2bdc2613d7b7