[ARM] 4365/1: Add AC97 clock to s3c2443 machine

This adds the ac97 clock to the s3c2443 machine files. It seems to
have been simply missed out previously.

Signed-off-by: Graeme Gregory <gg@opensource.wolfsonmicro.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>