ALSA: hdspm - Enable AES32 in hdspm_get_wc_sample_rate

This patch adds AES32 specific code to hdspm_get_wc_sample_rate() to
query the wordclock frequency.

Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>