The function typedefs we were using are only present when using the
dynamic loader, which means compilation breaks for code directly
using the cuda SDK.
To fix this, let's just duplicate the function typedefs locally.
These are not going to change.
The header guards were unnecessarily non-standard and the c file
inclusion trick means the files dont't have standard licence
headers.
Based on a patch by: Martin Vignali <martin.vignali@gmail.com>
We have a pattern of wrapping CUDA calls to print errors and
normalise return values that is used in a couple of places. To
avoid duplication and increase consistency, let's put the wrapper
implementation in a shared place and use it everywhere.
Affects:
* avcodec/cuviddec
* avcodec/nvdec
* avcodec/nvenc
* avfilter/vf_scale_cuda
* avfilter/vf_scale_npp
* avfilter/vf_thumbnail_cuda
* avfilter/vf_transpose_npp
* avfilter/vf_yadif_cuda
