[!HAVE_SYS_SOUNDCARD_H]: Define dummies.  Fixes build without sys/soundcard.h

diff --git a/src/midi.c b/src/midi.c
index 684f6de..11fb154 100644
--- a/src/midi.c
+++ b/src/midi.c
@@ -128,7 +128,33 @@ seqbuf_dump ()
   _seqbufptr = 0;
 }
 
-#endif
+#else /* !HAVE_SYS_SOUNDCARD_H */
+
+gint
+get_midi_channel ()
+{
+  return 0;
+}
+
+gint
+get_midi_prognum ()
+{
+  return 0;
+}
+
+gint
+get_midi_port ()
+{
+  return 0;
+}
+
+void
+seqbuf_dump ()
+{
+}
+
+#endif /* !HAVE_SYS_SOUNDCARD_H */
+
 /**
  * Close the sequencer device
  *