Remove WiFi related methods from NetworkManagementService

These are no longer necessary, since WiFi manages its own details.

Bug: 30041228
Change-Id: Ia3824da43367ae74d3f3a204318cfe5470d74957
Test: Compiles
(cherry picked from commit 212b95f587f4af637fb2429f29f7d0add1bd251f)
2 files changed