[RTC]    Add the s3c serial rtc driver model install.
[DETAIL] The linux is not install the s3c interal serial rtc device by default,
         but it support the s3c rtc device. So It need we add the s3c_device_rtc
         to the ok6410_devices array.
[TEST]   Make uImage, then mount the nfs filesystem.First set the system time,
         runl "hwclock -w" command save the system time, then reboot look the system time is or not save.