You will need to install the openmp package for voxl which can be found here http://voxl-packages.modalai.com/stable/.
The easiest way to do this would be to follow these steps:
Edit the /etc/opkg/opkg.conf file and change the last line from
src/gz modalai http://voxl-packages.modalai.com/dists/apq8096/stable/binary-arm64/to
src/gz modalai http://voxl-packages.modalai.com/stable/
opkg install openmp
Redit the /etc/opkg/opkg.conf file to change the last line back to the original i.e.
src/gz modalai http://voxl-packages.modalai.com/dists/apq8096/stable/binary-arm64/
Let me know if there are any issues.