Deprecate & remove IsCtrSpecific in favor of IsAnon

In Podman 1.6.3, we added support for anonymous volumes - fixing
our old, broken support for named volumes that were created with
containers. Unfortunately, this reused the database field we used
for the old implementation, and toggled volume removal on for
`podman run --rm` - so now, we were removing *named* volumes
created with older versions of Podman.

We can't modify these old volumes in the DB, so the next-safest
thing to do is swap to a new field to indicate volumes should be
removed. Problem: Volumes created with 1.6.3 and up until this
lands, even anonymous volumes, will not be removed. However, this
is safer than removing too many volumes, as we were doing before.

Fixes #5009

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

libpod/container_commit.go

@@ -137,7 +137,7 @@ func (c *Container) Commit(ctx context.Context, destImage string, options Contai
 				if err != nil {
 					return nil, errors.Wrapf(err, "volume %s used in container %s has been removed", v.Name, c.ID())
 				}
-				if vol.IsCtrSpecific() {
+				if vol.Anonymous() {
 					importBuilder.AddVolume(v.Dest)
 				}
 			}