dist/common/scripts/scylla_setup: skip running rest of the check when the disk detected as used
dist/common/scripts/scylla_setup: skip running rest of the check when the disk detected as used

Don't need to run check when we already detected the disk as used.

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