cuda: ready to use dllapi (dynamical loading cuvid)
cuda: add cuda headers and src(only used funcs tested) from dllapi tool

https://github.com/wang-bin/dllapi
Clang based mkapi tool in dllapi is not good enough. The types may be
different with those in headers if platform changed.
BTW, NVIDIA's version macros are designed genius!
FIXME: cuMemcpyDtoHAsync link error if force cuda version 0301
compat: AVCodecID for FFmpeg < 1.0
update ffmpeg for maemo script.