HID: asus: Add support for T100 touchpad

Add support for the Asus T100 touchpad in multi-touch mode (rather
then mouse emulation mode). It turns out that the Asus T100 touchpad
is identical to the already supported i2c-hid Asus touchpads, so
adding support for it was easy.

The only significant difference is that the reported x-coordinates
range on the T100 touchpad is somewhat lower then the range on the
already supported touchpads.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>