ARM: dts: exynos: Add support of bus frequency using VDD_INT for exynos3250-rinato

This patch adds the bus device-tree nodes of INT (internal) block
to enable the bus frequency scaling. The following sub-blocks share
the VDD_INT power source:
- LEFTBUS (parent device)
- RIGHTBUS
- PERIL
- LCD0
- FSYS
- MCUISP / ISP
- MFC

The LEFTBUS is parent device with devfreq ondemand governor
and the rest of devices depend on the LEFTBUS device.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>