Revert "Input: synaptics - use dmax in input_mt_assign_slots"

This reverts commit 6ab17a8484f03c188a93713369912f1545eb26e9 since it,
according to Benjamin, causes issues with slot assignment:

E: 15.669119 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
E: 15.954242 0003 002f 0000 # EV_ABS / ABS_MT_SLOT 0
E: 15.954242 0003 0039 0505 # EV_ABS / ABS_MT_TRACKING_ID 505
E: 15.954242 0003 0035 3851 # EV_ABS / ABS_MT_POSITION_X 3851
E: 15.954242 0003 0036 4076 # EV_ABS / ABS_MT_POSITION_Y 4076
E: 15.954242 0003 003a 0034 # EV_ABS / ABS_MT_PRESSURE 34
E: 15.954242 0001 014a 0001 # EV_KEY / BTN_TOUCH 1
E: 15.954242 0003 0000 3851 # EV_ABS / ABS_X 3851
E: 15.954242 0003 0001 4076 # EV_ABS / ABS_Y 4076
E: 15.954242 0003 0018 0034 # EV_ABS / ABS_PRESSURE 34
E: 15.954242 0001 0145 0001 # EV_KEY / BTN_TOOL_FINGER 1
E: 15.954242 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
... (bunch of regular events)...
E: 16.020614 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
E: 16.043601 0003 0035 3873 # EV_ABS / ABS_MT_POSITION_X 3873
E: 16.043601 0003 0036 3903 # EV_ABS / ABS_MT_POSITION_Y 3903
E: 16.043601 0003 003a 0050 # EV_ABS / ABS_MT_PRESSURE 50
E: 16.043601 0003 0035 3032 # EV_ABS / ABS_MT_POSITION_X 3032
E: 16.043601 0003 0036 3832 # EV_ABS / ABS_MT_POSITION_Y 3832
E: 16.043601 0003 003a 0044 # EV_ABS / ABS_MT_PRESSURE 44
E: 16.043601 0003 0000 3032 # EV_ABS / ABS_X 3032
E: 16.043601 0003 0001 3832 # EV_ABS / ABS_Y 3832
E: 16.043601 0003 0018 0044 # EV_ABS / ABS_PRESSURE 44
E: 16.043601 0001 0145 0000 # EV_KEY / BTN_TOOL_FINGER 0
E: 16.043601 0001 014d 0001 # EV_KEY / BTN_TOOL_DOUBLETAP 1
E: 16.043601 0000 0000 0000 # ------------ SYN_REPORT (0) ----------
E: 16.068837 0003 002f 0001 # EV_ABS / ABS_MT_SLOT 1
E: 16.068837 0003 0039 0506 # EV_ABS / ABS_MT_TRACKING_ID 506
E: 16.068837 0003 0035 3912 # EV_ABS / ABS_MT_POSITION_X 3912
E: 16.068837 0003 0036 3743 # EV_ABS / ABS_MT_POSITION_Y 3743
E: 16.068837 0003 003a 0056 # EV_ABS / ABS_MT_PRESSURE 56
E: 16.068837 0003 002f 0000 # EV_ABS / ABS_MT_SLOT 0
E: 16.068837 0003 0035 3026 # EV_ABS / ABS_MT_POSITION_X 3026
E: 16.068837 0003 0036 3708 # EV_ABS / ABS_MT_POSITION_Y 3708
E: 16.068837 0003 003a 0052 # EV_ABS / ABS_MT_PRESSURE 52
E: 16.068837 0003 0000 3026 # EV_ABS / ABS_X 3026
E: 16.068837 0003 0001 3708 # EV_ABS / ABS_Y 3708
E: 16.068837 0003 0018 0052 # EV_ABS / ABS_PRESSURE 52
E: 16.068837 0000 0000 0000 # ------------ SYN_REPORT (0) ----------

Slot 0 and 1 gets inverted in the second report above, which
introduces a cursor jump. The problem is that this cursor jump is
often enough to leave the current widget, and X sends the
scrolling events to whoever is now under the cursor.

Reported-by: Benjamin Tissoires <[e-mail]>
Reported-by: Hans de Goede <[e-mail]>

drivers/input/mouse/synaptics.c

···
 #define X_MAX_POSITIVE 8176
 #define Y_MAX_POSITIVE 8176
 
-/* maximum ABS_MT_POSITION displacement (in mm) */
-#define DMAX 10
-
 /*****************************************************************************
  *	Stuff we need even when we do not want native Synaptics support
  ****************************************************************************/
···
 		pos[i].y = synaptics_invert_y(hw[i]->y);
 	}
 
-	input_mt_assign_slots(dev, slot, pos, nsemi, DMAX * priv->x_res);
+	input_mt_assign_slots(dev, slot, pos, nsemi, 0);
 
 	for (i = 0; i < nsemi; i++) {
 		input_mt_slot(dev, slot[i]);