[ARM] 4551/1: s3c24xx: fix wrong virtual address offsets

This patch reduces 36-bit offset to 32-bit offsets. The 36-bit
offsets makes virtual addresses wraps when added to 32-bit base.

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>