ALSA: HDA patch_via.c: cleanup

* add extra parenthesis to make code more readable
* use kzalloc() for alloc+zero rather than kcalloc()
* ensure that AUTO_SEQ_* starts at 0

Signed-off-by: Harald Welte <HaraldWelte@viatech.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>