Fix default init config override for nova-compute

The config_template overrides for nova compute were loading units in that
were supposed to force nova compute to start after several over services
however this was rendering several unit entries for things service
properties that don't exist. This change converts the config_template
override into an "after_targets" list fixes the service config so that it
starts nova-compute in the order we're expecting. This will also put the
config_template overrides back into the user space allowing folks to do
what they need with the override options without having to know about our
set defaults.

Depends-On: https://review.openstack.org/634057
Change-Id: Iefd5ed5aa5b7cfb07b129784ae1706efd036e291
Signed-off-by: Kevin Carter <kevin@cloudnull.com>

defaults/main.yml

@@ -471,11 +471,7 @@ nova_libvirtd_debug_log_filters: "3:remote 4:event 3:json 3:rpc"
 
 nova_api_metadata_init_overrides: {}
 nova_api_os_compute_init_overrides: {}
-nova_compute_init_overrides:
-  Unit:
-    ? libvirtd.service
-    ? syslog.target
-    ? network.target
+nova_compute_init_overrides: {}
 nova_conductor_init_overrides: {}
 nova_consoleauth_init_overrides: {}
 nova_novncproxy_init_overrides: {}
@@ -515,6 +511,10 @@ nova_services:
     start_order: 6
     execstarts: "{{ nova_bin }}/nova-compute"
     execreloads: "/bin/kill -HUP $MAINPID"
+    after_targets:
+      - libvirtd.service
+      - syslog.target
+      - network.target
   nova-conductor:
     group: nova_conductor
     service_name: nova-conductor