msg: remove comparison operators for sockaddr_storage

We don't need these at all, it turns out.

Signed-off-by: Sage Weil <sage@inktank.com>
Merge pull request #1895 from ceph/wip-sock-cmp

msg: remove comparison operators for sockaddr_storage

Reviewed-by: Loic Dachary <loic@dachary.org>