usb: gadget: midi2: Dynamically create MIDI 1.0 altset descriptors

usb: gadget: midi2: Dynamically create MIDI 1.0 altset descriptors

This patch extends MIDI 2.0 function driver to deal with more MIDI1
Jacks depending on the given Block configuration.

For MIDI 1.0, we take the configuration given in Function Block 0, and
create MIDI Jacks and Endpoints depending on the definition there.
That is, when more UMP Groups are defined in the Block 0, the
corresponding MIDI1 Jacks will be created.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20230725062206.9674-4-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>