ARM: dts: exynos: Add audio clocks configuration for Snow Chromebook

Currently the audio subsystem clocks are not configured properly on Snow
and sound is not working. The MAX98095 CODEC is not getting its master clock
on the MCLK pin connected to the SOC's CLKOUT GPIO. This patch adds CLKOUT
and other clocks configuration so HDMI audio can also be supported.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>