init_kill_services_test: don't always try to kill hwservicemanager

When HIDL is not supported, hwservicemanager will not be running and may
not even be installed on the device.

Ignore-AOSP-First: Disabling HIDL internally first. Will cherry-pick
these test CLs after.

Test: init_kill_services_test
Bug: 218588089
Change-Id: Iae41e35e4669dd62c99ab9f138fc419be2f5fa29