service: Don't shutdown the VM when agent terminates

The semantic around the agent is that it should be a passive
component, hence it should not implicitly shut down the VM.

Instead, we expect the kata-runtime to be responsible for this,
using the appropriate VM interface to stop it.

Fixes #449

Depends-on: github.com/kata-containers/tests#1101

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: James O. D. Hunt <james.o.hunt@intel.com>

kata-agent.service.in

@@ -1,3 +1,9 @@
+#
+# Copyright (c) 2018-2019 Intel Corporation
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
 [Unit]
 Description=Kata Containers Agent
 Documentation=https://github.com/kata-containers/agent
@@ -10,5 +16,4 @@ StandardOutput=tty
 Type=simple
 ExecStart=@bindir@/@kata-agent@
 LimitNOFILE=infinity
-ExecStop=/bin/sync ; /usr/bin/systemctl --force poweroff
-FailureAction=poweroff
+ExecStop=/bin/sync