Input: elantech - ignore high bits in the position coordinates

Input: elantech - ignore high bits in the position coordinates

commit e938fbfd4a7ac829d48b767c4dc365535d5c4f97 upstream.

In older versions of the elantech hardware/firmware those bits always
were unset, so it didn't actually matter, but newer versions seem to
use those high bits for something else, screwing up the coordinates
we report to the input layer for those devices.

Signed-off-by: Florian Ragwitz <rafl@debian.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>