ASoC: AC97: S3C2443: Remove unused driver

Since, we have generic AC97 controller driver and all the machines
have moved to that, there is no need for old s3c2443-ac97.c to exist.

Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>