[ARM] JIVE: Remove duplicated mtd includes

Removed duplicated include file <linux/mtd/mtd.h> and <linux/mtd/partitions.h>
in arch/arm/mach-s3c2412/mach-jive.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>