Only write out uwsgi configs when deploying API services

Previously this would always happen for Nova and Cinder even if n-api
and c-api were not enabled on the host respectively.

This change stops this by placing both calls write_uwsgi_config behind
is_service_enabled checks.

Change-Id: I997685da771736dbad79bcfe4b00dbc63bd6d6b6
diff --git a/lib/nova b/lib/nova
index 9aae2c4..8109446 100644
--- a/lib/nova
+++ b/lib/nova
@@ -488,8 +488,13 @@
 
     iniset $NOVA_CONF upgrade_levels compute "auto"
 
-    write_uwsgi_config "$NOVA_UWSGI_CONF" "$NOVA_UWSGI" "/compute"
-    write_uwsgi_config "$NOVA_METADATA_UWSGI_CONF" "$NOVA_METADATA_UWSGI" "" "$SERVICE_LISTEN_ADDRESS:${METADATA_SERVICE_PORT}"
+    if is_service_enabled n-api; then
+        write_uwsgi_config "$NOVA_UWSGI_CONF" "$NOVA_UWSGI" "/compute"
+    fi
+
+    if is_service_enabled n-api-meta; then
+        write_uwsgi_config "$NOVA_METADATA_UWSGI_CONF" "$NOVA_METADATA_UWSGI" "" "$SERVICE_LISTEN_ADDRESS:${METADATA_SERVICE_PORT}"
+    fi
 
     if is_service_enabled ceilometer; then
         iniset $NOVA_CONF DEFAULT instance_usage_audit "True"