ARM: dts: exynos: Update PMU node with CLKOUT related data

This patch extends nodes of PMU system controller on Exynos4210, 4x12,
5250 and 5420 SoCs with newly defined properties used by Exynos CLKOUT
driver.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>

diff --cc arch/arm/boot/dts/exynos4210.dtsi
Simple merge

diff --cc arch/arm/boot/dts/exynos4x12.dtsi
Simple merge

diff --cc arch/arm/boot/dts/exynos5250.dtsi
Simple merge

diff --cc arch/arm/boot/dts/exynos5420.dtsi
Simple merge