ALSA: hda/intel: Workaround for WALLCLK register for loongson controller

On loongson controller, the value of WALLCLK register
is always 0, which is meaningless, so we return directly.

Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Yingkun Meng <mengyingkun@loongson.cn>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://lore.kernel.org/r/185df71ef413ab190460eb377703214ee7288aeb.1686128807.git.siyanteng@loongson.cn


Signed-off-by: Takashi Iwai <tiwai@suse.de>