[host1x] Improve FFmpeg error handling (#2643)

This improves the FFmpeg error handling.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/2643
Co-authored-by: MaranBr <maranbr@outlook.com>
Co-committed-by: MaranBr <maranbr@outlook.com>

src/video_core/host1x/codecs/decoder.cpp

@@ -38,6 +38,10 @@ void Decoder::Decode() {
     // Receive output frames from decoder.
     auto frame = decode_api.ReceiveFrame();
 
+    if (!frame) {
+        return;
+    }
+
     if (IsInterlaced()) {
         auto [luma_top, luma_bottom, chroma_top, chroma_bottom] = GetInterlacedOffsets();
         auto frame_copy = frame;