pNFS: Mark layout for return if return-on-close was not sent

If the layout return-on-close failed because the layoutreturn was never
sent, then we should mark the layout for return again.

Fixes: 9c47b18c

 ("pNFS: Ensure we do clear the return-on-close layout stateid on fatal errors")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>