db: Migrate "volume glance metadata" APIs to enginefacade
db: Migrate "volume glance metadata" APIs to enginefacade

Migrate volume glance metadata-related APIs from the legacy enginefacade
to the modern context-based enginefacade.

Change-Id: I71c2f3bfbfac7452ba317728078d2aaecc817c7c
Signed-off-by: Stephen Finucane <4725dc7f3632bf126d9fbdc30c347e91e8d2fe16@redhat.com>

openstack/cinder,openstack/cinder,mahak/cinder,mahak/cinder