Currently, for AWS instances in `is_supported_instance_class()` other than
i3* and *gd (for example: m5d), scylla_io_setup neither provides
preconfigured values for io_properties.yaml nor runs iotune nor fails.
This silently results in a broken io_properties.yaml, like so:
disks:
- mountpoint: /var/lib/scylla
Fix that.
Closes#9660