arm64: dts: qcom: sdm845: move bus clock to mdp node for sdm845 target

Move the bus clock to mdp device node,in order to facilitate bus band
width scaling on sdm845 target.

The parent device MDSS will not vote for bus bw, instead the vote will
be triggered by mdp device node. Since a minimum vote is required to
turn on bus clock, move the clock node to mdp device from where the
votes are requested.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20210803101657.1072358-2-dmitry.baryshkov@linaro.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>