ARM: clps711x: Add support for SYSCON driver

This patch adds support for SYSCON driver for CLPS711X targets.
At this time there are no users for this driver, but it is will
be used as start point to use in CLPS711X drivers and remove
<mach/xx> dependencies.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Olof Johansson <olof@lixom.net>