Use number of scan to load the right amount of data in compact viirs reader.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>
Merge branch 'unstable' of /data/proj/SAF/GIT/mpop into unstable
Add some debugging info about missing pixels in viirs_sdr.

Signed-off-by: Martin Raspaud <martin.raspaud@smhi.se>