If the touchpad is suspended and resumed (e.g. lid switch), the initial slot
state may be out of sync. If a touch happened while the touchpad was suspended
and the next touch down is on exactly the same x and/or y coordinate, our
touch point would still have the coordinates of the most recently seen touch
(i.e. before touchpad suspend). This could cause a pointer jump or test case
failures.

The real-world impact of this is minimal, putting the finger down in exactly
the same spot is virtually impossible. It could cause a test case failure in the
lid_disable_touchpad() test though, the second touch sequence was on the same
y coordinate and the touch location for that whole sequence was x/0.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>