ARM: SMDK2443: Enable AC97 device

Add AC97 controller to platform devices and initialize the AC97 gpios.

Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>