ALSA: ice1712: add suspend support for ICE1712 chip

Add suspend/resume support for ICE1712 chip.
Card-specific subdrivers need to enable it and provide callbacks that suspend/resume the codecs.

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>