udev-rules: use sd_device_set_sysattr_value() to write sysfs attribute

udev-rules: use sd_device_set_sysattr_value() to write sysfs attribute

Then, we can avoid that files outside of sysfs are written by udev ATTR key.

This also makes
- logs failure in udev_resolve_subsys_kernel(),
- failure in sd_device_get_syspath() critical, as that should not happen,
- cache the value to be write when running on test mode, to make it
  shown by OPTIONS="dump" or obtained by ATTR match token.