scollectd to ignore histogram
scollectd to ignore histogram

In the first stage of adding the histogram support, collectd will ignore
those metrics. A specific support will be added in a different patch.

Signed-off-by: Amnon Heiman <ed5fc74c4692051ad0b19749fd7cea6ec2d74b9e@scylladb.com>

dreamsxin/seastar,scylladb/seastar,scylladb/seastar,cloudius-systems/seastar,syuu1228/seastar,scylladb/seastar,syuu1228/seastar,syuu1228/seastar,dreamsxin/seastar,dreamsxin/seastar,avikivity/seastar,avikivity/seastar,avikivity/seastar,cloudius-systems/seastar,cloudius-systems/seastar