clk: samsung: Fix m2m scaler clock on Exynos542x

The TOP "aclk400_mscl" clock should be kept enabled all the time
to allow proper access to power management control for MSC power
domain and devices that are a part of it. This change is required
for the scaler to work properly after domain power on/off sequence.

Fixes: 318fa46c ("clk/samsung: exynos542x: mark some clocks as critical")
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>