mds: ignore session RENEWCAPS if state not open|stale
mds: ignore session RENEWCAPS if state not open|stale

This avoids breakage where a renewcaps races with a session
being purged, for example.

ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph,ajnelson/ceph