nv-codec-headers: make x86 only
nv-codec-headers: make x86 only

These runtime-depend on libcuda and some other stuff which makes
it useless on any other architectures. It would be technically
possible to get it to work on ppc64le and *maybe* 32-bit ARM
(assuming nvidia ships CUDA for it) but that's a lot of extra
work for something we are not prepared for at all.

[ci skip]

necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages,necrophcodr/void-packages