Pass the struct fp_dev and user_data to fpi_ssm callbacks, so that we
might be able to get rid of the fpi_ssm_get_user_data(), and
fpi_ssm_get_dev() as most drivers just get those from the ssm anyway
in their callbacks.
Remove all the headers already included through "fp_internal.h" such as
<libusb.h> and <errno.h>, include "assembling.h" and "driver_ids.h" there
as well to avoid doing it in (almost) every driver.
Sensor width seems to be only 128 pixels and that's not enough
for scanning whole finger surface. Lower bz3_threshold to 25,
since for wrong finger score never goes above 10, but sometimes
for right finger score is below 40.
Some scanners provide hardware assistance in frame assemling, i.e.
horizontal and vertical offset to previous frame is provided. This
commit improves code to utilise that assistance. Sensors without
hardware assistance will use software algorithm, which was also
improved to do search in horizontal direction.