NFSv4.1: Handle session reset and bind_conn_to_session before lease check

We can't send a SEQUENCE op unless the session is OK, so it is pointless
to handle the CHECK_LEASE state before we've dealt with SESSION_RESET
and BIND_CONN_TO_SESSION.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>