[ARM] 3639/1: S3C2412: serial port support

Patch from Ben Dooks

Serial port support for the on-board UART blocks
on the Samsung S3C2412 and S3C2413 UARTs.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>