Do you execute these lines (listed in the newest tutorial) on your board? You should build tvm runtime with set(USE_OPENCL ON)
in config.cmake
git clone --recursive https://github.com/dmlc/tvm
cd tvm
cp cmake/config.cmake .
sed -i "s/USE_OPENCL OFF/USE_OPENCL ON/" config.cmake ## MODIFY config.cmake
make runtime -j4