crush: include CRUSH_V3, v2/v3 rules checks in dump_tunables()

Backport: firefly
Signed-off-by: Sage Weil <sage@inktank.com>
Merge pull request #2098 from ceph/wip-dump-new-crush

crush: include CRUSH_V3, v2/v3 rules checks in dump_tunables()

Reviewed-by: Joao Eduardo Luis <joao.luis@inktank.com>