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>