repair: Remove unused sub_ranges_max
repair: Remove unused sub_ranges_max

With the sub range iterator, it is not used anymore. Drop it.

scylladb/scylla,scylladb/scylla,avikivity/scylla,avikivity/scylla,duarten/scylla,duarten/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,duarten/scylla