networking mlnx journal fix image build

Author: assumptionsandg

etc/kayobe/kolla.yml

@@ -142,7 +142,7 @@ kolla_sources:
   neutron-server-plugin-networking-mlnx:
     type: git
     location: https://github.com/stackhpc/networking-mlnx.git
-    reference: stackhpc/{{ openstack_release }}
+    reference: journal-fix-backport
   nova-compute-plugin-networking-mlnx:
     type: git
     location: https://github.com/stackhpc/networking-mlnx.git