Input: rename INPUT_PROP_HAPTIC_TOUCHPAD to INPUT_PROP_PRESSUREPAD

Input: rename INPUT_PROP_HAPTIC_TOUCHPAD to INPUT_PROP_PRESSUREPAD

And expand it to encompass all pressure pads.

Definition: "pressure pad" as used here as includes all touchpads that
use physical pressure to convert to click, without physical hinges. Also
called haptic touchpads in general parlance, Synaptics calls them
ForcePads.

Most (all?) pressure pads are currently advertised as
INPUT_PROP_BUTTONPAD. The suggestion to identify them as pressure pads
by defining the resolution on ABS_MT_PRESSURE has been in the docs since
commit 20ccc8dd38a3 ("Documentation: input: define
ABS_PRESSURE/ABS_MT_PRESSURE resolution as grams") but few devices
provide this information.

In userspace it's thus impossible to determine whether a device is a
true pressure pad (pressure equals pressure) or a normal clickpad with
(pressure equals finger size).

Commit 7075ae4ac9db ("Input: add INPUT_PROP_HAPTIC_TOUCHPAD") introduces
INPUT_PROP_HAPTIC_TOUCHPAD but restricted it to those touchpads that
have support for userspace-controlled effects. Let's expand and rename
that definition to include all pressure pad touchpads since those that
do support FF effects can be identified by the presence of the
FF_HAPTIC bit.

This means:
- clickpad: INPUT_PROP_BUTTONPAD
- pressurepad: INPUT_PROP_BUTTONPAD + INPUT_PROP_PRESSUREPAD
- pressurepad with configurable haptics:
  INPUT_PROP_BUTTONPAD + INPUT_PROP_PRESSUREPAD + FF_HAPTIC

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Acked-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://patch.msgid.link/20251106114534.GA405512@tassie
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>