[ARM] 2933/1: S3C2410 - fix serial port warnings

Patch from Ben Dooks

Fix the following warnings produced from
drivers/char/s3c2410.c.
drivers/serial/s3c2410.c:757: warning: 'clk' may be used uninitialized
drivers/serial/s3c2410.c:756: warning: 'clksrc' may be used uninitialized

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