Add touchscreen info for the Teclast Tbook 11 tablet. This includes info
for getting the firmware directly from the UEFI, so that the user does
not need to manually install the firmware in /lib/firmware/silead.

This change will make the touchscreen on these devices work OOTB,
without requiring any manual setup.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20210417173105.4134-1-hdegoede@redhat.com