[ALSA] cs5535audio: fix ACC_BM[x]_CMD register handling

According to 6.3.2.7 of the cs5535/cs5536 data sheets, the ACC_BM[x]_CMD
registers are only 8 bits wide.  This driver treats them as 32 bits wide,
and also has bits in the wrong place.  Simple fix to the definitions.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>