Atmel mxt devices can report one finger for each T9 reportid.
Therefore, this range can be used to report the max number of MT-B slots
to userspace instead of assuming a fixed 10.

Note that mxt_initialized() must complete early, since the input_dev
properties now depend on values in the object table.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>