[ARM] MINI2440: remove duplicated #include

Remove duplicated #include('s) in
  arch/arm/mach-s3c2440/mach-mini2440.c

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

arch/arm/mach-s3c2440/mach-mini2440.c

@@ -48,8 +48,6 @@
 #include <plat/mci.h>
 #include <plat/udc.h>
 
-#include <plat/regs-serial.h>
-
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand.h>
 #include <linux/mtd/nand_ecc.h>