osd: prevent old clients from using tiered pools

If the client is old and doesn't understand tiering, don't let them use a
tiered pool.  Reply with EOPNOTSUPP.

Fixes: #8714
Backport: firefly
Signed-off-by: Sage Weil <sage@redhat.com>
(cherry picked from commit 0190df53056834f219e33ada2af3a79e8c4dfb77)