Revert "Input: synaptics - allocate 3 slots to keep stability in image sensors"

This reverts commit 63c4fda3c0bb841b1aad1298fc7fe94058fc79f8 as it
causes issues with detecting 3-finger taps.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100481
Cc: stable@vger.kernel.org
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

drivers/input/mouse/synaptics.c

@@ -1199,7 +1199,7 @@ static void set_input_params(struct psmouse *psmouse,
 					ABS_MT_POSITION_Y);
 		/* Image sensors can report per-contact pressure */
 		input_set_abs_params(dev, ABS_MT_PRESSURE, 0, 255, 0, 0);
-		input_mt_init_slots(dev, 3, INPUT_MT_POINTER | INPUT_MT_TRACK);
+		input_mt_init_slots(dev, 2, INPUT_MT_POINTER | INPUT_MT_TRACK);
 
 		/* Image sensors can signal 4 and 5 finger clicks */
 		__set_bit(BTN_TOOL_QUADTAP, dev->keybit);