Solution;
Under VPS edit /etc/fstab,
nano /etc/fstab
and insert below lines,
mount /dev/loop0 -o noexec,nosuid,rw /dev/tmpFS /tmp
mount /dev/loop0 /dev/tmpFS -o noexec,nosuid,rw
Now run command below,
mount -obind,nosuid,noexec,nodev,rw /usr/tmp /tmp
You /tmp is mounted now with noexec