ALSA: ice1712: wm8766: Remove some unused functions

Removes some functions that are not used anywhere:
snd_wm8766_set_power() snd_wm8766_set_master_mode()

This was partially found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ice1712/wm8766.h

@@ -155,8 +155,6 @@ struct snd_wm8766 {
 void snd_wm8766_init(struct snd_wm8766 *wm);
 void snd_wm8766_resume(struct snd_wm8766 *wm);
 void snd_wm8766_set_if(struct snd_wm8766 *wm, u16 dac);
-void snd_wm8766_set_master_mode(struct snd_wm8766 *wm, u16 mode);
-void snd_wm8766_set_power(struct snd_wm8766 *wm, u16 power);
 void snd_wm8766_volume_restore(struct snd_wm8766 *wm);
 int snd_wm8766_build_controls(struct snd_wm8766 *wm);