ceph.spec: update ceph description

Fixes: #5835
Signed-off-by: Sage Weil <sage@inktank.com>
debian: update ceph description

Fixes: #5835
Signed-off-by: Sage Weil <sage@inktank.com>
Merge pull request #1628 from ceph/wip-5835

update package descriptions

Reviewed-by: Josh Durgin <josh.durgin@inktank.com>