rawmidi: Extensions for tied device and substream inactive flag

rawmidi: Extensions for tied device and substream inactive flag

This is the enhancements of rawmidi API for the new feature added in
6.14 kernel: the indication of a tied device and the inactive flag for
the selected substream.

The new function is added for obtaining the tied device,
snd_rawmidi_info_get_tied_device().

And the new bit flag is defined for indicating the inactive
substream, SNDRV_RAWMIDI_INFO_STREAM_INACTIVE, which is exposed via
snd_rawmidi_info_get_flags().

Signed-off-by: Takashi Iwai <tiwai@suse.de>