decklink: Avoid sending 0x0 frame to libobs

When the mode is set to auto, the API sometimes send frames with 0x0
size. Without filtering such frames, which causes libobs to output error
messages.

plugins/decklink/decklink-device-instance.cpp

@@ -187,6 +187,9 @@ void DeckLinkDeviceInstance::HandleVideoFrame(
 	currentFrame.height = (uint32_t)frame->GetHeight();
 	currentFrame.timestamp = timestamp;
 
+	if (currentFrame.width == 0 || currentFrame.height == 0)
+		return;
+
 	obs_source_output_video2(
 		static_cast<DeckLinkInput *>(decklink)->GetSource(),
 		&currentFrame);