video: Add NV12_10LE40 pixel format
This pixel format is a fully packed variant of NV12_10LE32,
a luma pixel would take 10bits in memory, without any
filled bits between pixels in a stride. The color range
follows the BT.2020 standard.
In order to get a better performance in hardware memory
operation, it may expend the stride, append zero data at the
end of echo lines.
Pack function by Nicolas Dufresne.
https://bugzilla.gnome.org/show_bug.cgi?id=795462
Signed-off-by: Nicolas Dufresne <nicolas@ndufresne.ca>
Signed-off-by: ayaka <ayaka@soulik.info>