Input: synaptics - enable InterTouch for the ThinkPad P1 G3

Input: synaptics - enable InterTouch for the ThinkPad P1 G3

Noticed this while trying to debug some unrelated issues: this laptop has
the ability to use rmi4 but doesn't by default. So let's fix that.

Tested locally, including mouse buttons, on my ThinkPad P1 G3. This might
also enable the X1 Extreme G3, but I don't have such a system to test
locally (presumably Mark can chime in if that's the case).

Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20220909202127.141761-1-lyude@redhat.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>