lmsensors: remove unused service file

* Upstream ships a systemd service file sensord.service now,
  so we don't need this anymore.
* Install lm_sensors.service and fancontrol.service to support systemd systems.
  lm_sensors.service: Initialize hardware monitoring sensors.
  fancontrol.service: Start fan control, if configured.

Signed-off-by: Li Xin <lixin.fnst@cn.fujitsu.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>