test: add mad test

test/mad.cpp

@@ -0,0 +1,14 @@
+#include <mad.h>
+
+int main()
+{
+    AEDI_EXPECT(mad_version[0] != '\0');
+    AEDI_EXPECT(mad_build[0] != '\0');
+
+    mad_stream stream = {};
+    mad_stream_init(&stream);
+    AEDI_EXPECT(stream.error == MAD_ERROR_NONE);
+    mad_stream_finish(&stream);
+
+    return 0;
+}