Split updatable/non-updatable Wifi APIs into separate directories

This creates a clearer boundary between what is updatable
(part of the Wifi module) and what is not updatable (outside
the module).

Bug: 176105484
Test: compiles
Merged-In: Ia95e300da9286d79ee57c285c3bfa88ecc98e326
Change-Id: I656786c81c832611fc308ea3e42571a90df3de1c
26 files changed