arm64: dts: qcom: sdm845: Add the missing clock on the videocc

We're transitioning over to requiring the Qualcomm Video Clock
Controller to specify all the input clocks.  Let's add the one input
clock for the videocc for sdm845.

NOTE: Until the Linux driver for sdm845's video is updated, this clock
will not actually be used in Linux.  It will continue to use global
clock names to match things up.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200203103049.v4.14.Id0599319487f075808baba7cba02c4c3c486dc80@changeid


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>