remove code not used

zhangmeng

2019-11-21 9b12b43b25fd5a476205bc693be0cf836c281bc1

 csrc/thirdparty/ffmpeg/include/libavutil/hwcontext_cuda.h

@@ -41,6 +41,7 @@
 */
typedef struct AVCUDADeviceContext {
    CUcontext cuda_ctx;
    CUstream stream;
    AVCUDADeviceContextInternal *internal;
} AVCUDADeviceContext;