Boosting performance with mkl-dnn

I was wondering whether mkl-dnn (https://github.com/intel/mkl-dnn ) can boost up TVM performance or not ?

I think it should. I’m testing the same model with different optimization frameworks, and some of them (that integrate mkldnn) outperform current tvm implementation. It would be great to have it integrate in tvm as well.

It’s discussed in this pr.