fix mxnet amalgamation (#96)
fix mxnet amalgamation (#96)


imai-lm/nnvm,piiswrong/nnvm,jermainewang/nnvm,imai-lm/nnvm,ZihengJiang/nnvm,jermainewang/nnvm,ZihengJiang/nnvm,imai-lm/nnvm,piiswrong/nnvm,piiswrong/nnvm,jermainewang/nnvm,ZihengJiang/nnvm