ARM: dts: Add support max77802 PMIC for exynos based Peach boards

Exynos5420 based Peach Pit and Exynos5800 based Peach Pi boards
uses a Maxim 77802 power management IC to drive regulators and
its Real Time Clock. This patch adds support for this chip.

These are the device nodes and pinctrl configuration that
are present on the Peach pit DeviceTree source file in the
the Chrome OS kernel 3.8 tree.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Tested-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>