commit 10d90030 upstream.

The touchpad of Lenovo Thinkpad L480 reports it's version as 15.
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>