[ARM] S3C64XX: Fix missing definition of s3c64xx_init_io()

The function s3c64xx_init_io was missing from <plat/cpu.h>
and was masked by the SMDK6410 having an local definition.

Fix by removing the SMDK6410 variant and adding it to the
relevant <plat/cpu.h> file.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

arch/arm/mach-s3c6410/mach-smdk6410.c

@@ -64,8 +64,6 @@ struct map_desc smdk6410_iodesc[] = {};
 static struct platform_device *smdk6410_devices[] __initdata = {
 };
 
-extern void s3c64xx_init_io(struct map_desc *, int);
-
 static void __init smdk6410_map_io(void)
 {
 	s3c64xx_init_io(smdk6410_iodesc, ARRAY_SIZE(smdk6410_iodesc));

arch/arm/plat-s3c/include/plat/cpu.h

@@ -47,6 +47,7 @@ extern void s3c24xx_init_irq(void);
 extern void s3c64xx_init_irq(u32 vic0, u32 vic1);
 
 extern void s3c24xx_init_io(struct map_desc *mach_desc, int size);
+extern void s3c64xx_init_io(struct map_desc *mach_desc, int size);
 
 extern void s3c24xx_init_uarts(struct s3c2410_uartcfg *cfg, int no);