ALSA: ASoC: Au12x0/Au1550 PSC Audio support

Audio for Au12x0/Au1550 PSCs in AC97 and I2S mode, for ASoC v1 framework.

- DBDMA, AC97 and I2S drivers
- sample AC97 machine code (Db1200)

Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Liam Girdwood <lg@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>