[WIFI] Clarify getConfiguredNetworks behavior for Carrier Apps

Carrier privileged apps will have a partial exemption post-Q to
receive a set of configurations which they created (but no others).

Clarify documentation.

Bug: 112205095
Test: N/A
Change-Id: I0d5e44155f0db40de0c2ca554d29cb6cd1e40f3d