OpenCV 3.1.0 contrib fails to build on ARM64

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Building on ARMV8 platform I get:

 [ 29%] Building CXX object modules/dnn/3rdparty/protobuf/CMakeFiles/libprotobuf.dir/src/google/protobuf/descriptor.cc.o
In file included from /home/test/opencv_contrib-3.1.0/modules/dnn/3rdparty/protobuf/src/google/protobuf/stubs/atomicops.h:59:0,
                 from /home/test/opencv_contrib-3.1.0/modules/dnn/3rdparty/protobuf/src/google/protobuf/stubs/once.h:81,
                 from /home/test/opencv_contrib-3.1.0/modules/dnn/3rdparty/protobuf/src/google/protobuf/descriptor.cc:53:
/home/test/opencv_contrib-3.1.0/modules/dnn/3rdparty/protobuf/src/google/protobuf/stubs/platform_macros.h:61:2: error: #error Host architecture was not detected as supported by protobuf
 #error Host architecture was not detected as supported by protobuf