[ALSA] virtuoso: allow both CS5381 and CS5361

Rename all CS5381 symbols to CS53x1 because they can also be used for
Xonar models with a CS5361.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>