TouchpadInputMapper: set reports_pressure hardware property

This will tell the Gestures library whether a touchpad reports pressure,
allowing it to disable pressure thresholds for touchpads that don't.

Bug: 292051746
Bug: 281907436
Test: with https://crrev.com/c/4794689 patched in libchrome-gestures,
      try tapping to click on the Lenovo P12 Pro keyboard pack touchpad
Change-Id: I9d7fdb40cf20ee4f8261a6b0e5bf94c58017749e