[FFmpeg-cvslog] avcodec/nvenc: only push cuda context on encoder close if encoder exists

ffmpeg | branch: release/3.3 | Timo Rothenpieler | Wed Aug 30 21:12:23 2017 +0200| [bab4cb3fb55e32d2f01bfb8c06f8e9fbd2d3f65d] | committer: Timo Rothenpieler avcodec/nvenc: only push cuda context on encoder close if encoder exists Signed-off-by: Timo Rothenpieler

[FFmpeg-cvslog] avcodec/nvenc: only push cuda context on encoder close if encoder exists

ffmpeg | branch: master | Timo Rothenpieler | Wed Aug 30 21:12:23 2017 +0200| [0e995eac2035ecd3c4c61cccdbc8cec478441779] | committer: Timo Rothenpieler avcodec/nvenc: only push cuda context on encoder close if encoder exists Signed-off-by: Timo Rothenpieler