Reduce log level for ovo_rpc when using apic_aim

When the aim_mapping policy driver is configured (along with
the apic_aim mechanism driver), a lot of the following messages
are seen in the neutron logs:

This handler is supposed to handle AFTER events, as in 'AFTER it's
committed', not BEFORE. Offending resource event: port, after_update.

The neutron code logs this at error level but allows the execution
to progress. This does not break functionality.

Neutron is right in flagging this, but as far as the apic_aim mechanism
driver is concerned, this behavior is per design since it sends out port
notifications in the pre-commit phase.

Change-Id: Id201f421a676af7c822a182e0ee87f034678e2d7

gbpservice/neutron/plugins/ml2plus/patch_neutron.py

@@ -56,6 +56,17 @@ def get_current_session():
         return
 
 
+from neutron.plugins.ml2 import ovo_rpc
+
+
+# The following reduces the ERROR log level for a message
+# which is seen when a port_update even is sent. The
+# port_update is intentionally sent in the pre_commit
+# phase by the apic_aim mechanism driver, but is not
+# what neutron expects and hence it flags it.
+ovo_rpc.LOG.error = ovo_rpc.LOG.debug
+
+
 from neutron.callbacks import registry