Update MKLDNN to v1.2. (#4316)

* Update MKLDNN to v1.2.

* Change class to struct.

* Change to struct.
Co-authored-by: Robert Kimball <robert.kimball@intel.com>
Co-authored-by: Sang Ik Lee <sang.ik.lee@intel.com>

cmake/external_mkldnn_v1.cmake

@@ -18,12 +18,12 @@ include(ExternalProject)
 
 # Includes blas 3.8.0 in mkldnn
 set(NGRAPH_MKLDNN_SHORT_VERSION 1)
-set(NGRAPH_MKLDNN_FULL_VERSION 1.1.1.0)
+set(NGRAPH_MKLDNN_FULL_VERSION 1.2.0.0)
 set(NGRAPH_MKLDNN_MKLML_ASSET_VERSION "v0.21")
-set(NGRAPH_MKLDNN_VERSION "v1.1.1")
+set(NGRAPH_MKLDNN_VERSION "v1.2")
 set(NGRAPH_MKLDNN_MKLML_VERSION "2019.0.5.20190502")
 set(NGRAPH_MKLDNN_MKLML_WIN32_VERSION "2020.0.20190813")
-set(NGRAPH_MKLDNN_GIT_TAG "v1.1.1")
+set(NGRAPH_MKLDNN_GIT_TAG "v1.2")
 
 #------------------------------------------------------------------------------
 # Fetch and install MKL-DNN

src/ngraph/runtime/cpu/cpu_runtime_context.hpp

@@ -36,7 +36,7 @@
 
 namespace mkldnn
 {
-    class primitive;
+    struct primitive;
 }
 
 namespace ngraph

src/ngraph/runtime/cpu/pass/cpu_mkldnn_primitive_build.hpp

@@ -35,7 +35,7 @@
 
 namespace mkldnn
 {
-    class primitive;
+    struct primitive;
 }
 
 namespace ngraph