touchpad: ignore the tap motion threshold if fingers > slots
Do so on the synaptics serial touchpads at least, they're known to cause cursor jumps when the third finger is down. Not detecting a tap move means three-finger taps get more reliable on these touchpads. This change affects gestures who now effectively have to wait for the tap timeout to happen. It's a trade-off. https://bugs.freedesktop.org/show_bug.cgi?id=101435 https://bugzilla.redhat.com/show_bug.cgi?id=1455443 Signed-off-by:Peter Hutterer <peter.hutterer@who-t.net>