[ALSA] sparc dbri: fixed setting of burst size after reset

A proper way to set DBRI's burst size. The size must be set after
each chip reset.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>