include conv_op_impl.h from conv_dnnlowp_op.cc (#22458)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/22458

To make sure template instantiation.

Reviewed By: jianyuh

Differential Revision: D16094183

fbshipit-source-id: 7861df0b303bec42ab80a53477c4b608edebb61d
diff --git a/caffe2/quantization/server/conv_dnnlowp_op.cc b/caffe2/quantization/server/conv_dnnlowp_op.cc
index d2774d4..2536580 100644
--- a/caffe2/quantization/server/conv_dnnlowp_op.cc
+++ b/caffe2/quantization/server/conv_dnnlowp_op.cc
@@ -10,6 +10,7 @@
 #endif
 
 #include "caffe2/core/tensor_int8.h"
+#include "caffe2/operators/conv_op_impl.h"
 #include "caffe2/utils/cpuid.h"
 
 #include <fbgemm/src/RefImplementations.h>