Currently snitch drivers register themselves in class-registry with all
sorts of construction options possible. All those different constuctors
are in fact "config options".
When later snitch will declare its dependencies (gossiper and system
keyspace), it will require patching all this registrations, which's very
inconvenient.
This patch introduces the snitch_config struct and replaces all the
snitch constructors with the snitch_driver(snitch_config cfg) one.
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>
633746b87d