Fix log_collector decoding for Nova placement

This makes sure that the Nova placement WSGI logs are tracked in the
log_messages metric.

Change-Id: I3410f06fff24a44295b5c206e4532241f4e22ed9
diff --git a/nova/meta/heka.yml b/nova/meta/heka.yml
index 2ff45c8..bf4f3c6 100644
--- a/nova/meta/heka.yml
+++ b/nova/meta/heka.yml
@@ -19,7 +19,7 @@
       module_file: /usr/share/lma_collector/decoders/apache_wsgi_log.lua
       module_dir: /usr/share/lma_collector/common;/usr/share/heka/lua_modules
       config:
-        logger: openstack.nova_placement
+        logger: openstack.nova
         apache_log_pattern: >-
           %v:%p %h %l %u %t \"%r\" %>s %D %O \"%{Referer}i\" \"%{User-Agent}i\"
     {%- endif %}