input: Implement two-fingers natural scrolling (enabled by default)

input touchpad settings header:
- Implement two-fingers natural scrolling (enabled by default)
- Sets scrolling with 2 fingers on the touchpad making
  the content to move in the same direction as the finger.

input preflet:
- Implement 2 fingers natural scrolling

input mouse:
- Handle and provide new settings for 2 finger natural scrolling

input mouse mm:
- Implement two-finger natural scrolling feature
- Implement natural scrolling for two-finger scrolling completely
  separated from reverse scrolling for egde scrolling only.

Change-Id: Idf673ec34a424b20183ed90761f297340d521526
Reviewed-on: https://review.haiku-os.org/c/haiku/+/9919
Reviewed-by: Adrien Destugues <[email protected]>
Tested-by: Commit checker robot <[email protected]>

headers/private/input/touchpad_settings.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2001-2009, Haiku, Inc. All Rights Reserved.
+ * Copyright 2001-2025, Haiku, Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef TOUCHPAD_SETTINGS_H
@@ -25,6 +25,7 @@ typedef struct {
 	int32  trackpad_acceleration;
 
 	bool	scroll_reverse;
+	bool	scroll_twofinger_natural_scrolling;
 } touchpad_settings;
 
 
@@ -40,7 +41,8 @@ const static touchpad_settings kDefaultTouchpadSettings = {
 	30,
 	65536,
 	65536,
-	false
+	false,
+	true
 };
 
 #define TOUCHPAD_SETTINGS_FILE "Touchpad_settings"