Revert "Temporarily disable init_kill_services_test."

This reverts commit bd68757d.

Reason for revert: reland test

The test now reboots after it is completed, in case there is some state it doesn't catch locally, and servicemanager restarts more of the system.

Change-Id: I1d6d021f75ef091aa7d6973b80ed162253514697
Fixes: 156380383
Test: atest init_kill_services_test # several times on cf, check logs to confirm system finishes in clean rebooted state