Fixed crash when checking if a sound file can be decoded by GME

src/modules/sound/lullaby/GmeDecoder.cpp

@@ -72,7 +72,7 @@ bool GmeDecoder::accepts(const std::string &ext)
 	static const std::string supported[] =
 	{
 		"ay", "gbs", "gym", "hes", "kss", "nsf",
-		"nsfe", "sap", "spc", "vgm", "vgz"
+		"nsfe", "sap", "spc", "vgm", "vgz", ""
 	};
 
 	for (int i = 0; !(supported[i].empty()); i++)