Input: synaptics_usb - Remove TrackPoint name trailing whitespace

The USB TrackPoint name string contains a space at the trailing end that
can cause confusion/difficulty when creating udev rules. Example:

 "Synaptics Inc. Composite TouchPad / TrackPoint (Stick) "

This patch removes the trailing space.

Signed-off-by: Bob Ross <pigiron@gmx.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>