ogg, ffmpeg: try to decode, even when the stream is not seekable

src/decoder/ffmpeg_plugin.c

@@ -210,7 +210,7 @@ ffmpeg_helper(struct input_stream *input, bool (*callback)(BasePtrs *ptrs),
 static bool
 ffmpeg_try_decode(struct input_stream *input)
 {
-	return input->seekable && ffmpeg_helper(input, NULL, NULL);
+	return ffmpeg_helper(input, NULL, NULL);
 }
 
 static enum decoder_command

src/decoder/oggflac_plugin.c

@@ -281,11 +281,6 @@ static struct tag *oggflac_TagDup(const char *file)
 
 static bool oggflac_try_decode(struct input_stream *inStream)
 {
-	if (!inStream->seekable)
-		/* we cannot seek after the detection, so don't bother
-		   checking */
-		return true;
-
 	return ogg_stream_type_detect(inStream) == FLAC;
 }
 

src/decoder/oggvorbis_plugin.c

@@ -364,11 +364,6 @@ static struct tag *oggvorbis_TagDup(const char *file)
 static bool
 oggvorbis_try_decode(struct input_stream *inStream)
 {
-	if (!inStream->seekable)
-		/* we cannot seek after the detection, so don't bother
-		   checking */
-		return true;
-
 	return ogg_stream_type_detect(inStream) == VORBIS;
 }