The volume variables is changed in mariadb chart.
It affects openstack helm gating job of mariadb, so we need to
change varible to
volume.use_local_path_for_single_pod_cluster.enabled.
Enable the local host path for mariadb data so if the container
is restarted during the gate jobs it can recover successfully.
Story: 2004702
Task: 33462
Depends-on: https://review.opendev.org/661955
Change-Id: Ib55779ddcbe7033da1900f5cd21de46543392d11
41ad002419