Add a library to support compiling ffmpeg.
Add a library to support compiling ffmpeg.

PiperOrigin-RevId: 387469334

GoogleCloudPlatform/PerfKitBenchmarker,GoogleCloudPlatform/PerfKitBenchmarker,GoogleCloudPlatform/PerfKitBenchmarker,GoogleCloudPlatform/PerfKitBenchmarker