Revert "Mainline wifi stack module"

This reverts commit 6f5338dd.

Reason for revert: Wifi services no longer plan to be a separate
APK/process for mainline. Will instead become a jar loaded from Apex.

Bug: 144722612
Test: Device boots up & connects to wifi networks.
Change-Id: I293e36973c4bdbd8bf9db2fcd78e61e6c38b39f4