metrics: Add make_counter() convenience overloads
metrics: Add make_counter() convenience overloads

To make them match the soon-to-be-deprecated make_derive()s. Also fix
the comment describing the method not to reference the derive peer, as
it's, well, going to be deprecated.

Signed-off-by: Pavel Emelyanov <c9a32589e048e044184536f7ac71ef92fe82df3e@scylladb.com>

syuu1228/seastar,syuu1228/seastar,syuu1228/seastar,avikivity/seastar,avikivity/seastar,scylladb/seastar,avikivity/seastar,scylladb/seastar,scylladb/seastar