ALSA: ump: Update substream name from assigned FB names

We had a nice name scheme in ALSA sequencer UMP binding for each
sequencer port referring to each assigned Function Block name, while
the legacy rawmidi refers only to the UMP Endpoint name.  It's better
to align both.

This patch moves the UMP Group attribute update functions into the
core UMP code from the sequencer binding code, and improve the
substream name of the legacy rawmidi.

Link: https://patch.msgid.link/20240729141315.18253-1-tiwai@suse.de


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