Input: trackpoint - add new trackpoint variant IDs

Add trackpoint variant IDs to allow supported control on Synaptics
trackpoints.

Signed-off-by: Vincent Huang <vincent.huang@tw.synaptics.com>
Link: https://lore.kernel.org/r/20200914120327.2592-1-vincent.huang@tw.synaptics.com
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>