Explicit Static Linking Failure

[0xcaff]

I'm trying to build the rust-ffmpeg-sys library with static linking.

What Happens

It fails to link statically and instead links some libraries dynamically because Config.statik doesn't fail if a static library couldn't be found.

https://github.com/meh/rust-ffmpeg-sys/blob/9056485f7fe4a42e3a68d08761b5a7817339da23/build.rs#L518-L521

What Should Happen

Terminal calls should throw if a static library is desired and couldn't be found. Maybe another function should be added with this behavior.

[hombit]

Any updates here?