Revert scylla-ami update in "scylla_setup: fix conditional statement of silent mode"
Revert scylla-ami update in "scylla_setup: fix conditional statement of silent mode"

This reverts part of commit 364c2551c892c57c7044a88760b522a42728b496. I mistakenly
changed the scylla-ami submodule in addition to applying the patch. The revert
keeps the intended part of the patch and undoes the scylla-ami change.

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