ARM: S3C64XX: Add samsung-time support for s3c64xx

Signed-off-by: Naour Romain <romain.naour@openwide.fr>
[tomasz.figa@gmail.com: tested on a Tiny6410 board]
Reviewed-and-Tested-by: Tomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>