HID: lenovo: set INPUT_PROP_POINTING_STICK

Set flags INPUT_PROP_POINTER and INPUT_PROP_POINTING_STICK for the trackpoint
integrated in Lenovo USB and Bluetooth keyboards. Libinput checks these flags
to enable features such as middle-button-scrolling by default.

Signed-off-by: Andreas Fleig <andreasfleig@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>