ACPI / device_sysfs: Clean up checkpatch errors

Cleaning up two existing checkpatch errors (and 2 warnings) in
device_sysfs.c since the file is being changed.

The change in acpi_device_setup_files() is changing spaces to a tab.

Signed-off-by: Betty Dall <betty.dall@hpe.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>