MKLDNN -Werror patch

diff --git a/3rdparty/mkldnn/cmake/platform.cmake b/3rdparty/mkldnn/cmake/platform.cmake
--- a/3rdparty/mkldnn/cmake/platform.cmake  2019-09-06 15:36:04.000000000 +0200
+++ b/3rdparty/mkldnn/cmake/platform.cmake  2019-12-25 09:13:46.934798193 +0100
@@ -63,7 +63,6 @@ if(MSVC)
     endif()
 elseif(UNIX OR MINGW)
     append(CMAKE_CCXX_FLAGS "-Wall -Wno-unknown-pragmas")
-    append_if_product(CMAKE_CCXX_FLAGS "-Werror")
     append(CMAKE_CCXX_FLAGS "-fvisibility=internal")
     append(CMAKE_C_FLAGS "-std=c99")
     append(CMAKE_CXX_FLAGS "-std=c++11 -fvisibility-inlines-hidden")