ARM: S3C24XX: Export s3c24xx_set_fiq for modules.

Allow s3c24xx_set_fiq() to be exported so that it can be used by modules
wanting FIQ support.

Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Simtec Linux Team <linux@simtec.co.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>