Describe the bug

Hi guys I would like to update ffmpeg library, but I'm facing this issues:

• CBS is now included into ffmpeg.
• cbs.h, cbs_h264.h and cbs_h265.h aren't copied into local64/include/libavcodec directory.
• Sunshine compilation fails during linking as cbs.o, cbs_h264.o and cbs_h265.o has been statically linked with ffmpeg. It conflicts with Sunshine's cbs.

Replacing current CBS implementation by ffmpeg one is a solution, only if I can fix the first issue.

I don't know how to add parameters to media-autobuild_suite so it can pass it to ffmpeg autoconf. It seems that options are into ffmpeg's CONFIG_EXTRA variable, but we can't set them externaly. Plus I don't know if it will copy right headers file to include directory.

To Reproduce
Only for development purpose, then we must use Sunshine's Workflows.

1. Execute media-autobuild_suite batch file
2. Create a sunshine-prebuild.zip file (see SunshineStream/Sunshine-Windows-Prebuilt workflow to replicate the process localy)
3. Comment CMakeList.txt sunshine-prebuild.zip
4. Copy sunshine-prebuild.zip into Sunshine's build directory
5. Execute Sunshine build.

Expected behavior
Sunshine build and run correctly.