ALSA: usb-audio: Rewrite registration quirk handling

A slight refactoring of the registration quirk code.  Now it uses the
table lookup for easy additions in future.  Also the return type was
changed to bool, and got a few more comments.

Link: https://lore.kernel.org/r/20200325103322.2508-2-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/quirks.h b/sound/usb/quirks.h
index 3afc01e..c76cf24 100644
--- a/sound/usb/quirks.h
+++ b/sound/usb/quirks.h
@@ -51,7 +51,6 @@ void snd_usb_audioformat_attributes_quirk(struct snd_usb_audio *chip,
 					  struct audioformat *fp,
 					  int stream);
 
-int snd_usb_registration_quirk(struct snd_usb_audio *chip,
-			       int iface);
+bool snd_usb_registration_quirk(struct snd_usb_audio *chip, int iface);
 
 #endif /* __USBAUDIO_QUIRKS_H */