arm64: dts: exynos: move MIPI phy to PMU node in Exynos5433

The MIPI phy is actually part of the Power Management Unit system
controller.  It does not have own address space, thus keeping the node
under soc causes warnings:

  exynos5433-tm2e.dtb: soc@0: video-phy: {'compatible': ['samsung,exynos5433-mipi-video-phy'], ...
    should not be valid under {'type': 'object'}

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20230127194057.186458-9-krzysztof.kozlowski@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>