As a rule, we don't deliver touch events containing only stationary
touchpoints. To fix QTBUG-52510 we added an exception in
1bd0ab7050 : if the velocity changed,
deliver it anyway. Now we need to do the same if the pressure changed.
Also, on the customer's hardware, pressure is indicated via ABS_MT_PRESSURE.
Change-Id: If7f7088df055d686cdd86967b999e38024f8170f
Fixes: QTBUG-77142
Reviewed-by: Laszlo Agocs <laszlo.agocs@qt.io>