VOL-1495: Fix OMCI result logging

Positional parameters do not log the way expected.

Change-Id: I6c85d73b6b9bfe5708fc8a1d83b43beb63855d4a
diff --git a/python/adapters/brcm_openomci_onu/onu_gem_port.py b/python/adapters/brcm_openomci_onu/onu_gem_port.py
index 8ecd192..1ee28a6 100644
--- a/python/adapters/brcm_openomci_onu/onu_gem_port.py
+++ b/python/adapters/brcm_openomci_onu/onu_gem_port.py
@@ -374,7 +374,7 @@
         failed_mask = omci_msg.get('failed_attributes_mask', 'n/a')
         unsupported_mask = omci_msg.get('unsupported_attributes_mask', 'n/a')
 
-        self.log.debug("OMCI Result: %s", operation, omci_msg=omci_msg,
+        self.log.debug("OMCI Result", operation=operation, omci_msg=omci_msg,
                        status=status, error_mask=error_mask,
                        failed_mask=failed_mask, unsupported_mask=unsupported_mask)