[ALSA] rawmidi: add get_port_info callback for sequencer information flags

Add a get_port_info callback to the snd_rawmidi_global_ops structure to
allow the USB MIDI driver to supply information flags for the sequencer
ports created by seq_midi.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
diff --git a/include/sound/rawmidi.h b/include/sound/rawmidi.h
index 584e73d..7dbcd10 100644
--- a/include/sound/rawmidi.h
+++ b/include/sound/rawmidi.h
@@ -46,6 +46,7 @@
 
 struct snd_rawmidi;
 struct snd_rawmidi_substream;
+struct snd_seq_port_info;
 
 struct snd_rawmidi_ops {
 	int (*open) (struct snd_rawmidi_substream * substream);
@@ -57,6 +58,8 @@
 struct snd_rawmidi_global_ops {
 	int (*dev_register) (struct snd_rawmidi * rmidi);
 	int (*dev_unregister) (struct snd_rawmidi * rmidi);
+	void (*get_port_info)(struct snd_rawmidi *rmidi, int number,
+			      struct snd_seq_port_info *info);
 };
 
 struct snd_rawmidi_runtime {