ALSA: usb-audio: fix BOSS ME-25 MIDI regression

The BOSS ME-25 turns out not to have any useful descriptors in its MIDI
interface, so its needs a quirk entry after all.

Reported-and-tested-by: Kees van Veen <kees.vanveen@gmail.com>
Fixes: 8e5ced83 ("ALSA: usb-audio: remove superfluous Roland quirks")
Cc: <stable@vger.kernel.org>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>