[ARM] 4775/1: s3c2410: fix compilation error if only s3c2442 cpu is selected

This patch fixes compilation error if only a machine with
s3c2442 cpu is selected but without s3c2440 cpu selected.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>