Input: elantech - use elantech_report_trackpoint for hardware v4 too

The Fujitsu H730 has hardware v4 with a trackpoint. This enables the
elantech_report_trackpoint for v4.

Reported-by: Stefan Valouch <stefan@valouch.com>
Tested-by: Stefan Valouch <stefan@valouch.com>
Tested-by: Alfredo Gemma <alfredo.gemma@gmail.com>
Signed-off-by: Ulrik De Bie <ulrik.debie-os@e2big.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>