extras/input_id: Correctly identify touchpads

BTN_TOUCH (as well as ABS_PRESSURE) is used not only by touchpads but
by touchscreens as well. The proper check for a touchpad is presence
of BTN_TOOL_FINGER and absence of BTN_TOOL_PEN (the latter to filter
out some tablets that use BTN_TOOL_FINGER).

Tablet matching should be on either BTN_TOOL_PEN or BTN_STYLUS.