Bokeh DX11 fix for Map/Unmap mismatch

Author: walbourn

LICENSE

@@ -1,6 +1,6 @@
                                The MIT License (MIT)
 
-Copyright (c) 2017-2020 Microsoft Corp
+Copyright (c) 2017-2021 Microsoft Corp
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of this 
 software and associated documentation files (the "Software"), to deal in the Software 

XDKSamples/Graphics/Bokeh/BokehEffect.cpp

@@ -271,6 +271,7 @@ namespace ATG
         D3D11_MAPPED_SUBRESOURCE mapping;
         context->Map(m_bokehCB.Get(), 0, D3D11_MAP::D3D11_MAP_WRITE_DISCARD, 0, &mapping);
         std::memcpy(mapping.pData, &cb, sizeof(cb));
+        context->Unmap(m_bokehCB.Get(), 0);
 
         context->VSSetConstantBuffers(0, 1, m_bokehCB.GetAddressOf());
         context->GSSetConstantBuffers(0, 1, m_bokehCB.GetAddressOf());