Blackfin: bf537-stamp: Register adav801 codec and ASoC machine driver

There is already an entry in the spi device table for the codec, but the
modalias was wrong.  Also the config symbol name for the codec is wrong,
so this is fixed as well.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Scott Jiang <scott.jiang.linux@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>