lib-storage: Fixed setting usable/unusable flags for shared namespaces. If a namespace doesn't have a root that exists, mark it as unusable. This avoids ACL plugin from autocreating that directory.
lib-storage: Fixed setting usable/unusable flags for shared namespaces.
If a namespace doesn't have a root that exists, mark it as unusable.
This avoids ACL plugin from autocreating that directory.

Distrotech/dovecot,Distrotech/dovecot,Distrotech/dovecot,Distrotech/dovecot,Distrotech/dovecot