[ARM] S3C24A0: Serial port definitions and driver support.

Add serial support for S3C24A0, based on current S3C2410
UART driver. It adds necessary new defines in regs-serial.h
for S3C24A0 and the code to support this device in
drivers/serial/s3c24a0.c

Signed-off-by: Sandeep Patil <sandeep.patil@azingo.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>