conflicting declaration ‘typedef struct LZ4_stream_t LZ4_stream_t’解決

問題參考及解決：https://github.com/ethz-asl/lidar_align/issues/16

終端輸入：
sudo mv /usr/include/flann/ext/lz4.h /usr/include/flann/ext/lz4.h.bak
sudo mv /usr/include/flann/ext/lz4hc.h /usr/include/flann/ext/lz4.h.bak

sudo ln -s /usr/include/lz4.h /usr/include/flann/ext/lz4.h
sudo ln -s /usr/include/lz4hc.h /usr/include/flann/ext/lz4hc.h